Garmin Forerunner 265 vs NRC App: which tracks running distance better

The Nike Running Club (NRC) app keeps cutting down my distance when compared to the results from my Garmin Forerunner 265. While it doesn’t make me any slower, it’s been bugging me for months. Since I’m not the only one annoyed by these discrepancies, I decided to look into the issue.

I’ve been using the NRC app for over a year now since it has great and free guided runs. However, being quite obsessed with different training data, I also track my runs with smartwatches – either an Apple Watch or a Garmin Forerunner 265.

While running shorter distances, time-based runs, doing intervals, or speed training, I haven’t noticed much of a difference, it’s the longer runs that are the source of frustration. Just last week, I ran my first ever 20km. But, when, according to Garmin, I was crossing the finish line, NRC insisted I was 250 meters short, so I couldn’t stop. If you’re a runner, you’ll understand – having that perfect round number is oddly satisfying.

Now, 250 meters is, actually, not that big of a deal. Sometimes, NRC cuts down half a kilometer or even a kilometer – especially if you are, let’s say, running in circles while waiting for the green traffic light.

I’m neither the first person nor the last one to complain about the issue, with runners all over the world pointing out the same problem.

“I’m frustrated by the way the NRC keeps cutting down my distance for runs. I have a Fitbit, which also uses my phone's GPS, and it’s always 0.5-1k ahead of what NRC reports my run distance to be. I run the same route pretty much every day, so it’s easy for me to tell when NRC is messing up,” one user complained on Reddit a while back.

Now, Garmin claims that GPS receivers are “extremely accurate.” Since tall buildings and densely populated areas can affect those receivers, it says Garmin GPS “are accurate to within 15 meters (49 feet) 95% of the time.”

The Garmin Forerunner 265 provides its users with GPS-based running distance, time, and pace. It also uses a multi-band GPS system, meaning that the receiver tracks more than one radio signal from each satellite to “reduce errors caused by environmental interference.”

Runners agree that running apps are not that accurate when it comes to tracking your jogs. NRC also utilizes GPS run tracking, so I guess it’s as good as my phone’s GPS.

Smartwatch tracking is more consistent

The issue, while rather new to me, is well-known to experts and athletes. One reason I fell in love with the NRC app is that its coaches call everyone, even an amateur like me, an athlete.

Most of them will tell you the same thing – a wearable’s GPS will be more accurate. One pundit told me it’s because a smartwatch has a built-in GPS. But, apparently, so does my iPhone 14 Pro Plus, so that doesn’t explain much.

The problem, then, might be the position of both GPS chips.

“The NRC app on an iPhone might cut off some distance compared to a smartwatch due to differences in how each device processes GPS data. Smartwatches are often worn on the wrist and may have a more consistent line of sight to GPS satellites, potentially offering more accurate tracking. In contrast, if a smartphone is carried in a pocket or an armband, its position may vary more, affecting the GPS signal and, thus, the accuracy of distance measurements,” a certified personal trainer and garagegympro.com founder, Andrew White, told me.

That did make the most sense to me, because, depending on the season, my phone is sometimes buried under a few layers of clothing while my smartwatch is always out there for me to see.

“Additionally, running apps and devices use different algorithms to smooth out GPS data and calculate the total distance. These algorithms account for erratic GPS signals by "guessing" your path between recorded points. The methodology and sensitivity of these algorithms can vary between apps and devices, leading to discrepancies in recorded distances,” he further explained.

These discrepancies, while they don’t make that much of a difference, can be really annoying for a scrupulous person like me. If you feel the same, here are a couple of things that you, according to Mr. White, can do:

Ensure both your smartphone and smartwatch are fully updated, as updates often include improvements to GPS tracking algorithms.

• Try to keep your smartphone in a stable position while running, such as in a secure armband.

• Consider running in areas with clear visibility to the sky to improve GPS signal strength.

• Calibrate your devices if they offer this feature, as calibration can help improve accuracy.

Yes, yes, the important thing is you are out there running. But what if you just ran your half-marathon, and your app is insisting you are 200 meters short?

My answer? I stopped (?) obsessing about it and now rely on Garmin for metrics since it seems to me more accurate while still following an NRC training plan. You can also sync your Garmin with the NRC app so it will display Garmin’s calculated distance. However, if you do that and press “Start” on the app at the same time, your runs will be doubled on the app, distorting your stats.