Don't buy a Fitbit or Pixel Watch if you care about swim tracking

About two weeks ago, I put on my swimsuit and jumped in the pool for my first lap swimming session in four years. In less than one length, it was obvious to me that nothing had changed: I still knew how to freestyle swim (even though I was immediately out of breath) and Fitbit trackers were still utterly useless at swim tracking.

I am currently wearing a Pixel Watch and using it to track my walks, random hikes, and, for the past couple of weeks, swims. And let me tell you one experience is not like the others. So if your preferred form of exercise involves doing back-and-forths in the pool, I wouldn’t recommend you get a Fitbit and I’d caution you against the Pixel Watch too; there are much better smartwatches for swimming out there.

Where are the swim stats, Fitbit?

As you can see in the left screenshot above, when I start tracking a walk or hike, I can see plenty of stats on my Pixel Watch‘s screen, from the total distance to the number of steps, heart rate, pace, calories, active zone minutes, and more. I can even customize the display setup to only show the stats I care about. But as the right screenshot shows, when I start a swim, all I can see is the elapsed time and, uh, that’s it. Just a stopwatch on the screen. No laps, distance, pace, heart rate, or anything of the sort. A $10 digital watch does the same thing. Heck, I could simply look at the wall clock in the pool and calculate the duration of my swim!

Things don’t get much better when I’m out of the pool and sync my exercise with my Pixel 7 Pro. The app shows me how many lengths I’ve swum and calculates the total distance. Those are all the proper swimming stats Fitbit deigns to give me. Any seasoned swimmer will tell you that they don’t need a fitness tracker for that; we already count laps in our heads and we can do the math. Multiplying by 50m or 100m isn’t rocket science.

What we need is pace, average duration per pool length, break duration, splits, a SWOLF score, and all of it clearly organized by swim stroke type. (I personally alternate freestyle and backstroke and I’m definitely faster at the former). Showing me total duration and distance is opaque and pointless; it doesn’t allow me to compare my stats, follow my progression, or learn anything interesting about my current swim. Runners, cyclists, and hikers have it so much better with Fitbit.

And yes, there are three other tabs of so-called stats, but none of them mean all that much for swimmers. Calories burned get two tabs for some reason, with a graph that is mildly interesting to follow my general progression and rest. Another tab shows heart rate zones, but I doubt they’re accurate because, for some reason, heart rate doesn’t appear to be tracked during swims. Wait, what?!

Where is the heart rate data, Fitbit?

For other exercise types, Fitbit measures and displays my heart rate in a detailed graph. For swimming? Nada. As I mentioned earlier, even the active minutes don’t appear to be accurate because no matter what I do — swim faster, slower, or rest — all my minutes are counted as “fat burn.” Even my first swim, when I struggled a lot, couldn’t breathe properly, and felt my heart jump out of my chest, was supposedly all spent in the lower “fat burn” zone. I know my body and I’m confident I hit the cardio zone repeatedly and peak heart rate multiple times.

It seems to me that, instead of relying on measured heart rate data from my smartwatch‘s built-in sensor, Fitbit is applying some old algorithm that looks at the swim’s duration and total distance, then assigns an average heart rate zone to the entire exercise, regardless of what I’m doing or how intense the exercise feels to my own heart.

I wore an Apple Watch on my second wrist the other day, just to see if the Pixel Watch was messing up my zones, and well, yes. According to the Apple Watch, I spent over 50 minutes above 149bpm, which should qualify as the “cardio” zone on my Pixel Watch. But according to my Fitbit stats, I was chilling in the “fat burn” zone nearly the entire time. In case you’re wondering, the two watches measure the same heart rate outside the pool, so it isn’t a matter of one of them being faulty.

Another quite telling proof is that heart rate data during the swim is completely missing from the day’s graph too. Check the screenshots below. I went for a swim around noon on Tuesday, July 25, and Thursday, July 27. Heart rate data is notably missing during those exercises (pointed out by the red arrows), so there is no way for me to tell how intensely I swam. At all.

And just in case you had any doubts, I reached out to Google and got confirmation: Fitbits and the Pixel Watch do not track heart rate during swims. Why? I don’t know.

Fitbit’s swim tracking is crap, get a Garmin instead

To be fair, this isn’t anything new. Fitbit’s swim tracking has been below par for years. Even back in 2016, when I was testing the Flex 2, I noticed that it failed at tracking any interesting details about swims. Seven years later, it still does. Fitbit displays the same stats now as it did in 2016. There should’ve been plenty of time to improve those algorithms and provide a better swim-tracking experience. Alas, nope.

The Pixel Watch’s only saving grace is the third-party Swim.com app. It measures most of the stats you need and seems accurate enough. But the data doesn’t sync back to Fitbit and integrate with the rest of your exercises, leaving you with another app to keep your eye on. (No, Swim.com doesn’t support Google Health Connect.)

That’s why I’d recommend you get another fitness tracker if you’re interested in tracking your swims and improving your pace. Garmin trackers are excellent for swimming and even a basic option like the Garmin Forerunner 55 ($199.99 at Amazon) will run swim laps around the best Fitbits or the Pixel Watch with superb info on the screen, while you swim.

Alternatively, if you want more apps and smarts, Apple has upped its swim capabilities and the latest Apple Watch Series 8 will show all your laps, swim styles, pace, and more. It still has some issues measuring laps and detecting wall flips, though, in my experience.

And finally, if you want to live in the future, the FORM swim goggles ($249 at Amazon) overlay your stats inside your goggles as you swim. I used to wear them when I was frequently swimming four years ago and, even though I disliked the narrow field of view, I found the experience of seeing all my stats in front of my eyes insanely awesome and useful. It was like having my own relentless coach, and it helped me push myself and improve my swim way more than glancing once or twice at a watch screen ever could. I still have it in my backpack so maybe I’ll take it for a spin on my next swim. I just wish Fitbit on my Pixel Watch could come anywhere near that.