Best power meters: Accurate and reliable options for getting the training data you need

The best power meter is a tool for objective measurement. Strain gauges and accelerometers located in the crank spider, crank arm, or the pedals measure exactly how hard, and fast, you are pushing through your legs. The results, expressed in watts, are then transmitted wirelessly to one of the best bike computers. This data is the basis for all modern cycling specific training.

Once you can measure power data, you can then start down a path such as our article covering how to train with a power meter. Or, for those who are just stepping into the world of using a power meter, another option might be our article about understanding FTP. To make it all work though, you need to start with a power meter and that's what this article is about.

I've been training with power for years and now I've had the chance to compare and contrast the different power meter options. I started by testing every power meter against other options on the same ride. When I was sure that the data provided was accurate, I then took a look at the rest of the experience of owning that power meter. There are power meter options that install at the crank—either in the spindle, the spider, or on the arms—and as pedals and each one has a different ownership experience. Keep reading to see what makes sense for you. 

Quick list

Josh Ross
Josh Ross

I've been training with power for years. I've spent much of that time looking for the best options and learning how to better utilize the products available. These are the power meters I think are the best choices for most people with a variety of needs. 

Best power meters available today

You can trust Cyclingnews Our experts spend countless hours testing cycling tech and will always share honest, unbiased advice to help you choose. Find out more about how we test.

Budget power meters

If you aren't looking to spend a fortune on a power meter then a single sided option is the best place to start. The specs on these will read as if they are as accurate as other options but that's not the whole picture. Single leg options work by measuring one leg and estimating the second based on the pedal stroke. Unfortunately, that can be significantly off as "typical leg-strength discrepancies amount to roughly 5% for most adults" according to Training and Racing with a Power Meter: Third Edition.

Despite that discrepancy, there can still be plenty of value in a single leg power meter. While the absolute number given won't necessarily match up to other power meters, a good product will still be consistent. If you only need a repeatable number, and are looking to save some money, this is a great option.

Best budget power meter

(Image credit: Josh Ross)

1. 4iiii Precision 3+ Left Side power meter

Best budget power meter

Specifications

Weight: 9 grams
Battery Life: 800 hours
Battery Type: CR2032 coin cell
Stated Accuracy: +/- 1%
Power Balance Measurement: Single leg only
Location: Left crank arm

Reasons to buy

+
Value pricing
+
Long battery life
+
Apple Find My Integration

Reasons to avoid

-
 Single leg only

4iiii has a long history of offering power meters attached to cranks with a range of different price points. For those looking to keep costs low, you'll need to start with a compatible Cannondale, FSA, Shimano, or SRAM crank then you'll pull off the left side crank arm and send it in. 4iiii will bond a 9 gram pod to the inside of the crank arm and send it back. If you’d rather not bother with the hassle of being without a crank arm then you can also purchase the system installed on a crank arm that matches what you have. It is a little more expensive that way but depending on your crank arm, it might not be much different.

Whatever you choose, the pod uses three strain gauges and is capable of measuring the known deflection for the cranks offered. Measurement accuracy is +/- 1% though you'll want to keep in mind that's only true for one leg. This is industry standard labelling but because your legs don't put out the same power it's less accurate than other systems that measure both legs. Still, despite what might be a less accurate overall number, it is perfectly repeatable and this is a great place to start riding with power. 

4iiii also offers a lot of other great features that make it worth consideration even for experienced power meter users. Chief among them, the brand new Apple Find My Integration. Any time the crank is at rest it's trackable through any iPhone and there's both no actual Airtag for a thief to remove and the relative safety of the fact that it's part of a crank. Apple is careful to say it's not a theft deterrent but should your bike go missing, it's a lot more likely you will find it with this system in place. Beyond that, there's also the 800 hour battery life, a long warranty, and IPX7 water resistance. 

Although this is a budget option, anyone who is good with repeatability vs perfect overall accuracy should consider it. 

⤴ Back to the top

Best budget power meter for a gravel bike

(Image credit: Josh Ross)

2. SRAM Apex Power crank upgrade

Best budget power meter for a gravel bike

Specifications

Weight: 40 grams
Battery Life: 400+ hours
Battery Type: AAA
Stated Accuracy: +/- 1.5%
Power Balance Measurement: Single leg only
Location: Spindle

Reasons to buy

+
Value pricing
+
SRAM AXS Web integration
+
AAA battery

Reasons to avoid

-
Single leg only
-
1x only

SRAM recently updated the Apex groupset and you can now get a 1x12 bike with either mechanical or electronic shifting at prices never before seen. Combine that with SRAM already having a reputation for gravel groupsets and 1x prowess, and you can expect that a lot of budget minded bikes are going to come from the factory with a SRAM Apex groupset. 

When it's time to upgrade a SRAM Apex bike to include a power meter, it makes sense to turn to SRAM. There are other options you could switch to but there's nothing easier or less expensive than the SRAM Apex crankarm power meter upgrade kit. You don't need a bearing puller or any specialised tools. Just loosen the non drive side, pull it and slide the new one in then torque it. You'll be riding again in only a few minutes and there's no compatibility issues since you already have an Apex crankset. 

With everything installed, the system resides in the spindle. You'll have +/- 1.5% accuracy, though just like any single leg system the overall number isn't as accurate, and SRAM makes things even easier by using a single AAA battery. No matter where you are in the world, it shouldn't be hard to find a AAA although with 400+ hours it won't be a regular need. 

SRAM also has one other big advantage and that is the SRAM AXS web dashboard. Once there is a connection established with your bike computer, you'll get the same kind of analysis for your power data you would otherwise have to pay for. Looking at your power curve and time in zone is easy and, although it's possible to use without also using SRAM components, the more you stay in the ecosystem, the more data you'll have available. 

If you don’t have a SRAM Apex groupset on your gravel bike, 4iiii likely covers the crank you do have.  

⤴ Back to the top

Power meter pedals

Placing a power meter within a pedal is the most difficult option for manufacturing but the easiest option for users. Moving pedals from one bike to another is never an issue, the only compatibility issue to consider is cleat choice, and it’s easy to understand where the power is being measured. 

The biggest downside to pedals is that you can’t easily change pedals if you want a different cleat system, and they are the most exposed option making them susceptible to damage. 

Best overall power meter

(Image credit: Josh Ross)
Best overall power meter

Specifications

Weight: 320 grams as measured for both pedals
Battery Life: 120 hours
Battery Type: LR44/SR44 (x4) or CR1/3N (x2)
Stated Accuracy: +/- 1%
Power Balance Measurement: Dual leg + stroke analysis
Location: Pedals

Reasons to buy

+
Simple installation
+
Garmin Connect
+
Transferrable spindle

Reasons to avoid

-
 Pedal is heavier with a less precise feeling 

The power meters I've used more than any others have been from Garmin. I've spent years going all the way back to the Garmin Vector 2 and never had a single issue. The Garmin RK200 is the latest in that line and everything that made the previous version great, has only gotten better. 

Part of why I've used these pedals so much, and why it makes sense for a lot of other people, is that using pedals is a very simple way to approach the challenge of locating a power meter. There are advantages to putting power in a crank but it can be a challenge to make sure that your frame will work and you can't always take a crank to a new bike. Pedals get rid of all those challenges and with the current generation of Garmin pedals the brand has even made it so you can transfer the spindle to a different pedal body. 

The RK200 is the Look compatible dual pedal version but you can swap things at a later date. If you'd prefer to start with a single leg at a lower price point, you can later upgrade to dual measurement. If you start with the Look compatible version, you can move the spindle to an SPD or an SPD-SL compatible version down the line. 

Whatever you end up with, Garmin has Garmin Connect and, like SRAM, rewards you for staying within the ecosystem. Record your ride with a Garmin head unit and you'll have access to the data showing what your power delivery looks like compared to the pedal stroke, pedal platform centre offset data to help find an optimal cleat placement, and seated vs standing data.  

The only thing that might stop you from choosing a Garmin pedal based power meter is the actual pedal part of it. It's good but there are better options out there. If you aren't part of the Garmin ecosystem you might not be able to access the extra data and a lighter more precise pedal is nice to use. 

If you are interested in more details, check out our full RK200 and XC200 Garmin pedal review

⤴ Back to the top

Best power meter pedals

(Image credit: Josh Ross)
Best power meter pedals

Specifications

Weight: 284 grams as measure for both pedals
Battery Life: 30 hours
Battery Type: Rechargable
Stated Accuracy: +/- 2%
Power Balance Measurement: Dual leg + stroke analysis
Location: Pedals

Reasons to buy

+
Lightweight
+
Solid positive retention
+
Long spindle
+
Low stack height

Reasons to avoid

-
Finicky installation process
-
Battery drains over time

The SRM X-Power road pedals weren't on my radar as something to pay attention to. They cost a bit more than the Garmin pedals and they don't have all the extra data. When I started riding with them though, I noticed something I didn't expect. The SRM X-Power road pedals feel better to ride with.

While Garmin pedals are excellent, as soon as you clip into the X-Power pedal you can feel how much more precise and solid the retention is. The lightweight fully aluminium construction feels precise and clip-in is very positive but never finicky. Despite sharing the same q-factor spec, the SRM pedals have more room between the edge of the pedal and the crank arm and there's a lower stack height. 

As I said in the larger review, SRM is a pedal that has power while Garmin is a power meter built into a pedal. If you put out more power and tend to ride harder, you might appreciate the pedal first approach that SRM has taken. That does mean losing out on some of the data Garmin offers but if you don't use a Garmin head-unit, you might not have access to that anyway. 

The reason you might want to reconsider the SRM X-Power offering is that some of the advantages of pedals disappear. The SRM installation process can be finicky and it's easy to not get the setup quite right. When that happens, the power isn't accurate. The low battery life might also be a consideration as 30 hours isn't that long compared to everyone else plus it drains even when off. Of course if you want to use Look cleats, the X-Power is SPD-SL only so that will make an easy choice. 

If you are looking for a power meter that just works and is easy to use, the Garmin pedals are a better choice. If you’d prefer really good pedals that happen to have a power meter, the SRM X-power is a better choice.

Read more details in our full SRM X-Power Road pedals review.

⤴ Back to the top

Best power meter pedals for a gravel bike

(Image credit: Josh Ross)
Best power meter pedals for a gravel bike

Specifications

Weight: 444 grams as measured for both pedals
Battery Life: 120 hours
Battery Type: LR44/SR44 (x4) or CR1/3N (x2)
Stated Accuracy: +/- 1%
Power Balance Measurement: Dual leg
Location: Pedals

Reasons to buy

+
Simple Installation
+
Garmin Connect
+
Transferrable spindle

Reasons to avoid

-
Batteries aren’t common

The Garmin Rally pedals are a platform and which specific version you start with doesn't change much. That means the details in the description of the Rally RK200 above all apply to the XC200. It's still a dual sided pedal based system with the same core power measurement features and the same extra info available through Garmin Connect when using a Garmin head unit. It's still exceptionally easy to change bikes or take your pedals. When it comes to gravel power pedals though, there's direct competition with SRM and the X-Power pedals in the SPD (MTB) configuration. 

While on-road, I rarely clip out and I love how precise and solid the lighter weight SRM pedals are, the X-Power doesn't have the same advantage off-road. The SRM pedal offering doesn't have a weight advantage off-road and if you are doing technical riding, you'll probably appreciate the lighter clip out on the Garmin Rally pedals. Instead, the bigger matchup is between the Garmin Rally pedals and a crank based system for off-road riding. 

Riding a gravel bike through technical trails can mean pedals take a serious beating. I've put thousands of miles on the XC200 and I've never had an issue but I also tend to ride gravel roads more than single track. If you hit your pedals on a regular basis, you might want to put your power meter elsewhere, such as in the crank or axle. What could also be an issue is finding the right batteries in some remote part of the world. The Garmin Rally XC200 still has an impressive 120 hour battery life but a SRAM crank system that uses a AAA could be worth considering if you often ride in far off places.

If you are interested in more detail, check out our full RK200 and XC200 Garmin pedal review.

⤴ Back to the top

Best power meter for precise cleat positioning

(Image credit: Josh Ross)
Best power meter for precise cleat positioning

Specifications

Weight: 276g combined weight as measured
Battery Life: 75+ hours
Battery Type: rechargable
Stated Accuracy: +/- 1%
Power Balance Measurement: True dual sided measurement
Location: Pedals

Reasons to buy

+
Dual sided entry
+
Easily swapped
+
The most customizable and precise cleat setup

Reasons to avoid

-
Lots of float is hard to get used to

The heart of the Wahoo Powrlink Zero power meter pedals is a Speedplay pedal design. The Wahoo contribution is to add a collar to the spindle that handles all the electronics. In terms of the physical design it means you don't need a pedal wrench to get these off, something that can be a challenge when travelling, but more than that it means these are the Speedplay pedals. 

Speedplay pedals have always been polarising and that hasn't changed. The pedal itself is incredibly minimal and allows for dual sided clip in. All the pieces that handle retention are instead located on the cleat side. In terms of weight, it's likely a draw but the cleats do last nearly forever. 

More important than how long the cleats last, they mount with four points of adjustment instead of three. That means you can be very precise in how the cleat mounts and there are a lot of options for adapting around injuries with shims or other adjustments. The whole system is also good for knee pain because it allows your foot to move around on the pedal far more than other systems. 

The downside of that movement, referred to as float, is a lot of people will say it's maddening. As I said, Speedplay pedals always generate strong opinions. There are very vocal supporters who can't stand riding other pedal systems. There are also a lot of people, myself included, who describe the Wahoo Powerlink system as feeling like you are riding on an ice cube. You'll have to decide where you fall on that continuum but if you have knee injuries it's likely you'll be a supporter.  

Read more details in our full Wahoo Powrlink Zero power meter pedals review

⤴ Back to the top

Power meter cranks

This section actually covers a few different types of power meters because power meter cranks have different mounting options. A company can choose to make use of the spindle, the spider, and the crank arms depending on the design. The advantage of choosing a crank based power meter is how integrated the system is. That integration means you barely notice it's there, it's highly protected, and you can use whatever pedals you want. The downside of that integration is that you need to understand bottom bracket standards, you may need a new bottom bracket, and that once you change bikes your new bike might not fit your power meter. Most power meter cranks are highly modular at this point so compatibility is becoming less of an issue but it is still worth considering. 

Also worth paying attention to is the language around single vs dual sided power measurement when it comes to power meter cranks. Most, though not all, cranks only measure the power of both legs. Unlike a single sided system the measurement is an accurate picture of the actual power you are generating but what might be missing is a clear picture of which leg is responsible for the power generation. If that's important to you, look for a system that has individual strain gauges for each leg.

Best Shimano compatible power meter

(Image credit: Josh Ross)

1. FSA Powerbox K-Force Team Edition

The best Shimano compatible power meter

Specifications

Weight: 135g power meter only
Battery Life: 300 hours
Battery Type: CR2450
Stated Accuracy: +/- 2%
Power Balance Measurement: Whole power, virtual balance
Location: Spider

Reasons to buy

+
Lightweight
+
Standard 110x4 bolt pattern
+
Self-extracting crank design

Reasons to avoid

-
Lacks true dual sided measurement
-
Heavy chain rings included

Shimano has power meters but right now, they are tough to get. That means if you've got a Shimano bike that didn't come with a power meter, you need another option. The 4iiii crank option is one way, but another direction to go is a spider based system from Power2Max and that's exactly what the FSA Powerbox K-Force Team Edition is. The difference is that by purchasing it in this configuration you get the NGeco paired with the K-Force Team Edition crankset. 

The FSA K-Force Team edition crankset is something I covered as part of the K-Force WE 12s review. Without the power meter it's a gorgeous carbon crankset with hollow arms and a decorative TeXtreme carbon weave. The arms are hollow and with an equally gorgeous machined spider it comes in at only 569 grams. It uses a 30mm spindle and installation is easy with a self extracting bolt system that uses two different hex heads and no need for any special tools. 

The Powerbox version takes that design and swaps out the one piece chainrings. In their place, the NGeco measures power from the spider with a pair of chain rings attached via a standard 110mm 4-bolt pattern. That standard bolt pattern is nice because it means you could actually use the system on a SRAM AXS bike if you changed over to compatible chainrings. Keep in mind though that there's no room for anything smaller than a 34T chainring so the 46/33 that SRAM uses won't work. On the other hand, if you are using it with a Shimano system you might also choose to swap to a nicer set of chainrings than what FSA includes in the purchase. 

The official specification for the NGeco is +/- 2% however, in my testing, it's no less accurate than other units in this list. Like other spider based systems though, it does limit the accuracy to whole power. The estimated right/left balance tracks well but doesn't seem to do a great job with being accurate against a true dual system. 

⤴ Back to the top

Best SRAM compatible power meter

(Image credit: Josh Ross)

2. SRAM RED AXS Power meter

Best power meter for SRAM AXS groupsets

Specifications

Weight: 261 grams including 46/33 chainrings
Battery Life: 200 hours
Battery Type: CR2032
Stated Accuracy: +/- 1.5%
Power Balance Measurement: Whole power, virtual balance
Location: Spider

Reasons to buy

+
SRAM AXS Web integration
+
Lightweight
+
Available gearing

Reasons to avoid

-
 Lacks true dual sided measurement 

2019 was when SRAM introduced the SRAM Red AXS groupset along with this power meter as an option. Part of that introduction was a completely new gearing strategy called x-range designed to limit the need to use the front derailleur. The relevance in this discussion is that it means the front chainrings use a 13-tooth jump (instead of Shimano standard 16-tooth) and they are smaller. That can make finding a third party power meter a challenge depending on your gearing choice. Sticking to a SRAM option for a SRAM bike makes everything very simple. 

Unlike the SRAM Apex power meter, SRAM Red AXS uses a spider based system that captures the full power output from both legs. The spec puts it at +/-1.5% accuracy but what it does not do is offer a true left and right measurement like Rotor or any of the pedals. What that means is that in my testing, it's not that accurate in estimating what leg is putting out the power at any given moment. If that's important to you, look at another system and you may have to sacrifice your preferred gearing.

There are other advantages to the spider based system though. SRAM actually integrates the power meter into the chainset and by doing so manages to get the overall weight down to 630 grams (170 mm, 50/37). Even more interesting than that though, the whole system is electronic only and that means even more data in SRAM AXS web.  

With the SRAM Red AXS power meter and a SRAM groupset, the level of detail available after a ride is unheard of. A quick glance shows that I can tell you how many times I shifted and into what gear. Then, because I'm also using the power meter, I can tell you what my average power was in that gearing combination. It's a level of detail you can't get without being a part of the SRAM ecosystem.

⤴ Back to the top

Lightweight dual sided power meter crank

(Image credit: Josh Ross)
Lightweight dual sided power meter crank

Specifications

Weight: 537g for crank arms in 172.5mm plus axle and 179g for the chainrings (716g total)
Battery Life: 250 hours
Battery Type: Rechargable
Stated Accuracy: +/- 1.5%
Power Balance Measurement: True dual sided measurement
Location: Spindle and crank arm

Reasons to buy

+
Direct mount chainrings use an elegant mounting system
+
Beautiful aluminium machining
+
Lightest true dual sided power meter crankset on the market

Reasons to avoid

-
Currently no working app
-
Missing some chainring options

The Rotor 2Inpower SL is an update to the previous 2Inpower that switches aluminium to a harder 7075 alloy. That harder material means less material needed and a 15% weight reduction compared to what was already a light weight power meter. Rotor then adds even more beautiful CNC work with a range of chainring options that use a direct mount system. Not only does that get the weight down to a combined 716 grams (172.5mm and 50/34 chainrings) but it also does away with the kind of screws that sometimes come loose and squeak. 

In fact, this piece might have been the best SRAM crank based power meter but right now Rotor doesn't have the full breadth of AXS gearing options in the catalogue. There's no technical reason though so you might consider going up in gearing a little and waiting. You could also swap to the 11-36 Rotor cassette and a 50/36 chainring as long as you have a newer SRAM XPLR rear derailleur. All that aside though, it's not the chainrings that makes the Rotor 2Inpower SL unique. 

What makes this crank based power meter unique is that it's true dual power measurement. There's a total of eight strain gauges. Four of the gauges measure measure power from the spindle. The other four strain gauges measure power in the drive side crank arm. That allows true right and left power measurement with no estimation. If you want to know exactly how much each leg is contributing to your power output that's what you need. If you are looking at other options from this list that match that performance you'd need to look at the pedal based systems. With the Rotor 2Inpower SL you get an exceptionally stiff crank and the freedom to use whatever pedals you'd prefer. 

You can find more details in our full Rotor 2Inpower SL review

⤴ Back to the top

Best power meter if you only want to buy once

(Image credit: Josh Ross)

4. SRM Origin Look Carbon

Best power meter if you only want to buy once

Specifications

Weight: 700g with Look carbon crank arms and aluminium 52/36 chainrings
Battery Life: 100+ hours
Battery Type: Rechargable
Stated Accuracy: +/- 1%
Power Balance Measurement: Whole power, virtual balance
Location: Spider

Reasons to buy

+
Completely modular design
+
Adjustable crank length
+
Wide range of available chainrings
+
Beautiful design

Reasons to avoid

-
Huge price in comparison to the competition

SRM can take credit for bringing power meters to the cycling world, but the brand has also been slow to evolve. There have been periods of time where SRM power meters came to market with comparatively higher prices and less features. As I write this though, the latest generation SRM PM9 is available with features like rechargeable batteries and magnetless cadence that now match the competition. In addition to that, the brand still has a history that no one else can match. 

That history matters because power meters are an expensive purchase. Bikes will come and go but your power meter can stick with you. SRM has been through the ups and downs of the bike industry and continues to be there. The brand regularly repairs customer products designed and built before newer companies even existed. That staying power doesn't only apply to customer service though. The latest generation PM9 is also a product with staying power. 

The PM9 uses eight strain gauges attached in pairs where the chainrings attach to the inner spider. Those pieces are what matters for power measurement but they aren't the only components in a crank. In most situations that means you have to match your needs to a current bike then hope your next bike is close enough that everything still works. SRM offers something better than that. 

Every single piece of an SRM PM9 system is modular. No matter what bike you move to and what your needs are in the future, you can change parts and keep your current power meter. There are choices for 24mm or 30mm spindles and 1x or 2x chainrings with options covering gearing all the way from the smallest SRAM AXS ranges up to the largest anyone is likely to need. There are even different crank arm options. Choose Look carbon and you can build a system weighing as little as 700 grams (252 grams for the arms) but you can also adjust crank length between 170, 172.5, and 175 mm without changing arms. Rotor comes close to this functionality but still can't match this level of customization. 

⤴ Back to the top

How to choose the best power meter

Before jumping into the decision tree of how to pick the best power meter for you, it's good to understand how they work, so we'll go right back to the basics. 

What is a power meter?

A power meter is a component that you fit to your bike (in one of a few specific available places) that measures the amount of power (in watts) that you are putting through the pedals to drive the bike forward. 

It transmits that measured data to a third-party device (a bike computer, a smartphone, etc) where it is displayed for immediate viewing and captured for post-ride analysis. 

This power data can then be used to inform your training sessions and highlight your progress over time. The book Training and Racing with a Power Meter, now in its third edition, is the definitive guide to using a power meter in cycling and the first paragraph in the introduction under "How you can get started" says it best:

"A cyclist who wants to reach a new threshold of achievement, a power meter is an invaluable tool. It can help you uncover hidden areas of weakness that never would have come to light through the use of a heart rate monitor or simple cyclometer (bike computer). Capturing a second-by-second diary of your ride that you can later download and analyze, a power meter is a data goldmine." 

How do power meters work?

Exactly how it works is largely irrelevant when buying, just as long as it does, but it all starts with strain gauges that measure flex within the components in which they are housed. Because the flex curve of the material is a known quantity, a brand can understand how much pressure it takes to cause that flex. Power meters measure watts though and watts are a measure of work over time. To get the other side of the equation, cadence is also measured. Those numbers are then combined to get a final output on your cycling computer.  

If you are also looking for the nuts and bolts definition, it has to start with the understanding that "Power = Force x Speed." A power meter is a device that measures both force and speed then completes the equation and reports that to a bike computer in watts. In most cases that means strain gauges and accelerometers taking measurements as you pedal. 

What is the best type of power meter?

When shopping for a power meter, one of the considerations is going to be where to physically locate it. All power meters will replace some other component on your bike so you have to decide what makes sense for you. The first thing you will want to think about is how transportable do you want it. 

If you need a highly portable power meter that will necessitate a pedal based system. Pedals are easy because you can take them off one bike and put them on the next without issues. If you travel regularly and use other bikes choose pedals. You will also want to choose pedals if you have a few bikes that you switch between and want to use only a single power meter. 

If you don't need as much portability, instead choose a system in your crank. This is also what you want to consider if you prefer pedals with a cleat system that is less common or want your power meter more protected than pedals. As you start to look at the crank instead, some options will take measurement from a crank arm, some from the spindle, and some from the spider. 

To decide where in the crank you want the measurement, your desire for true left right measurement is a good place to start. If that's important you need something that has strain gauges physically able to take measurements from each leg. One, possibly both, of them will be in a crank arm so make sure it has clearance with your frame. The other will be in the spider so make sure you can get the chainrings you prefer. If you are okay with a virtual left and right measurement that will open up your options to include only spider based systems. You will still want to consider available chainrings though and all crank based systems require bottom bracket compatibility consideration. 

Although I've given information you might consider as you choose where to place a power meter, there's no right answer. There is no absolute best place to measure power from. Given that I travel a lot and change bikes frequently, I tend to spend a lot of time using power meter pedals. When given the choice though I prefer a spider based system because they are very light and allow me to use different types of pedals. 

How accurate should your power meter be?

As you start to decide what power meter makes sense for you, one of the first things on your mind is likely to be accuracy. From a consumer point of view, there is a lot of debate around the idea of accuracy vs repeatability in power meters. If you only have one power meter and that's what you use in every situation it has to be repeatable and accuracy is less important. Despite that, most people have a desire for objective accuracy also. 

From the manufacturer point of view, accuracy is a big selling point. Every brand will tell you that the power meter that brand makes is the most accurate on the market and that you definitely need that accuracy. At the same time, there are different specs with regards to the promise of accuracy. Some options list +/- 1% accuracy while others say 1.5% or 2% accuracy. 

When I investigated those discrepancies, I found it was far less important than it initially seemed. SRM, Rotor, and Power2Max all said that when it comes to that accuracy spec, it's a bit of an estimate. When I had the chance to go even deeper with Rotor engineers, the brand talked about how it's very easy to put a strain gauge on a bench and find the accuracy. It's also quite simple to measure the accuracy of a cycling specific power meter if you only consider direct force through the centre of the pedal. Unfortunately that's not how pedalling a bike works. There is a lot of force you put into the pedal that doesn't directly translate into forward movement. Each brand handles that a little differently and that's why the stated percentage ends up being an estimate and less important than it seems. 

With that backstory in mind, what I did was check the power meters against each other. I rode with more than one power meter and looked for discrepancies. Given that I can't test two power meters at the same time at the same location, they will never be identical. Instead, I wanted to see that the peaks and valleys tracked and that the numbers were close. In my testing, I saw no difference between power meters with different stated accuracy numbers. That number might seem objective and important but that's not what I found. As you shop, look for what makes sense for you. Everything here is accurate. 

Should I choose a single or double sided power meter?

If you are really worried about accuracy in your power meter, this is actually the better question. Power meters that only measure the output of a single leg will not be as accurate as power meters that measure power from both legs. The confusing part of this is that the specs might still show a +/-1% accuracy.

What’s happening is that humans are not machines and your power measurement will not be perfectly even between legs. Single sided power meters will take measurement from one side then use software to estimate the otherside. That would be perfect if both sides were even but they aren’t. For me, the numbers show about a 2% strength advantage in my right leg. That means even if a power meter captures the measurement from my left leg perfectly, that number will not accurately represent the total power I am able to put out. Bottom line, a single leg power meter will be repeatable but not accurate when compared with a dual leg power meter. You will need to decide if the lower price is worth less accuracy when deciding between dual leg or single leg measurement options. 

For many people, it will make sense to start with a single leg power meter because of price. If you are looking for the best budget power meter, it will be single sided. If it's all you have and use, you would likely never know the difference so that won't be an issue. Also, many of the single leg systems are upgradeable at a later date if you decide you need more accuracy. 

As you make this choice, there is one consideration to keep an eye on. When a brand tells you that it measures both right and left leg power, that does not mean it is a true dual leg power meter. It's very obvious to understand that with a pedal you either have a dual leg system or a single leg system. It's less obvious with a crank based system. 

If you choose a crank based power meter then often there are strain gauges measuring the combined power from your left and right leg. You could define that as dual leg measurement but nothing is physically measuring how hard each leg is pushing. A system like that will be accurate for the whole number but may not show leg imbalances as well. If knowing exactly what each leg is doing is important to you then choose a system that has separate strain gauges for each leg.

Can I use Zwift without a power meter?

This question exists in a discussion about the best power meter because Zwift is a power based system. Your character moves forward depending on how hard you push on the pedals and that means a power measurement. For many people this is the introduction to using power measurement on a bike and if you are thinking about using Zwift understanding the requirements is a good place to start. 

The simple answer is that you do not need a power meter to ride on Zwift. You do need power measurement though and that means if you use a trainer without a power meter you need one that has Zwift compatibility. Any Zwift compatible trainer will have had the resistance curve mapped and, when combined with cadence and speed sensors, can take advantage of virtual power measurement. The result will be a relatively accurate power measurement tool and you can ride in Zwift with only that. It's also worth noting that anything on our list of the best smart trainers will also have power measurement built in. 

How did we test the best power meters?

I tested every power meter here against at least one other on the same ride by connecting each power meter to a different bike computer. During the rides I spent some time riding at a steady state as in flat riding, some time climbing at higher power levels, and I spent some time doing short bursts of power as in an interval. 

With that data I then used software to compare the output of the multiple power meters against one another. Power losses in the drivetrain will affect the reading of power meters, so no two power meters will ever report exactly the same number, but by looking for inconsistencies, I weeded out any inaccurate performers and settled on the list of accurate power meters shown above. The bare minimum for a power meter is reliable and accurate data so that was the starting place for every option here. 

Alongside that process of establishing power data reliability, I also looked at the rest of the ownership experience. Things like install difficulty, battery life and type of battery, and pricing. The options presented here offer a range of choice for different needs but everything is a quality product that will provide the data you need from the best power meter for you.

⤴ Back to the top

Josh Ross

Josh hails from the Pacific Northwest of the United States but would prefer riding through the desert than the rain. He will happily talk for hours about the minutiae of cycling tech but also has an understanding that most people just want things to work. He is a road cyclist at heart and doesn't care much if those roads are paved, dirt, or digital. Although he rarely races, if you ask him to ride from sunrise to sunset the answer will be yes.
Height: 5'9"
Weight: 140 lb.
Rides: Salsa Warbird, Cannondale CAAD9, Enve Melee, Look 795 Blade RS, Priority Continuum Onyx