I ran with my watch (and my phone) yesterday for the first time. I also had my Nike + app running at the same time for comparison. The watch was WAY OFF BASE. Calculations for distance and pace weren't even close. Will this be calibrated over time??

Hi dbwass,

It seems you are seeing unexpected results when using Apple Watch. The following article provides steps to calibrate Apple Watch, which may improve the quality of your activity results:

Calibrating your Apple Watch for improved Workout and Activity accuracy - Apple Support

You can calibrate your Apple Watch to improve the accuracy of your distance and pace measurements during walking or running workouts when GPS isn't available (such as when you walk or run outdoors without your iPhone, or use a treadmill).

1. Bring your iPhone and your Apple Watch.
2. Find an open, flat area outside that offers good GPS reception and clear skies.
3. Hold your iPhone in your hand, or attach it to your body with an armband (preferably) or waistband.
4. Open the Workout app on your Apple Watch, and choose Outdoor Walk or Outdoor Run.
5. Choose your goal, or select Open, and tap Start.
6. Walk or run at your normal pace for about 20 minutes.

If you can't accumulate 20 minutes of outdoor walking or running during one Workout session, you can accumulate 20 minutes over multiple outdoor walking or running Workout sessions with your iPhone. If you frequently walk or run at a variety of different speeds, it's best to accumulate 20 minutes of outdoor walking or running in the Workout app with your iPhone at each of the speeds you frequently walk or run at.

You don't need to do anything specific to start this calibration process. It can be done during a regular outdoor walking or running workout in the Workout app when you have your iPhone with you. And, whenever you use Apple Watch and iPhone to walk or run outside in the Workout app, it will continue to calibrate the accelerometer by learning your unique stride length at different speeds, and get more accurate over time.

This calibration process can also help improve the accuracy of your overall calorie estimations in many of the other workout categories in the Workout app, and the calorie, distance, Move, and Exercise estimations in the Activity app. However, it's not necessary to do this calibration process before using either the Activity or Workout apps.

Thank you for contributing to Apple Support Communities.

Take care,

Bobby_D

The watch needs the phone's GPS to measure distance. It uses that information over time to calibrate your stride length, so it can estimate s=distance and pace without the phone.

Mine has been very accurate (compared to Runkeeper, which was my app of choice). I don't have Nike to compare so I can't comment on it

Spanishblonde, have you tried calibrating the watch? When I did my first indoor run of about 3 miles, the watch calculated it to be almost 5 miles. The next day I did some running and walking outside, calibrating the watch, and when I did my next indoor run of 3 miles the watch was spot on. My indoor runs are on a track, not a treadmill, but I believe during calibration it accounts for your change in stride from walking to running.

Calibrating your Apple Watch for improved Workout and Activity accuracy - Apple Support

The watch, has to use the iPhone for GPS to get accurate location data. It needs that data to formulate pace, distance and actual steps. The watch has to learn from the iPhone for a while from what Apple have said, once it does, it should be much more accurate though it will never be 100% because it lacks GPS.

Same issue. Running with iPhone 6. Distance was measured approximately 10% to short compared to reality and iSmoothrun.

The even more annoying problem was the fact that shown pace had absolutely nothing to do with the measured distance and time.

I passed first kilometer mark around 7 minutes both values shown on watch like this but at this time the displayed pace value was 11:33 min/km.

Pace value was also constantly changing.

I think when running with attached phone there can be no excuse for not having accurate distance and pace.

nick101 wrote:

Check that the pace was not in miles rather than kilometres

All was correct. With metric settings the pace will always shown metric as well. The summary did show the correctly calculated pace as well.

I think the pace algorithm is either buggy or stupidly implemented. Even when we consider the mileage calculation has some errors, the distance/time ratio should fit.

Strange, because fitness is one of the most hyped features and for sure many people from Apple are runners.

I ran again this morning - distance and pace in the summary were correct. Pace during the run seemed right.

I'm using Runkeeper in parallel to provide a benchmark, and they seem to tie up pretty well. This is alos over a course whose distance I know.

There will be some differences in the rate at which GPS is polled for data, and the algorithms for calculating distance, but they should be as wide as you're seeing.

I ran the launch day w it, the main reason i purchased the watch was to use for running. I used mapmyrun which i was also running on my phone, i was disappointed that they didnt have a pace screen on the watch. So i switched to Nike+ and the pace seemed ok. I ran yesterday and attempted to use the work out app, the pace was WAY off, so I also than opened Underarmours Record watch app to see how that one would be, it was alot better, but im still not sold on the pace being accurate. my phone was running map my fitness the entire time and was accurate with the other 2 guys i ran with. My biggest questions is, what will be accurate with the PACE, that is huge for me, i want to be able to look down at my wrist to make sure Im pacing correctly. I have a big 10 mi run sunday, and I am hoping for a PR, so i really need to get this figured out so im not messing around w it while running.

22xxxWC wrote:

I have a big 10 mi run sunday, and I am hoping for a PR, so i really need to get this figured out so im not messing around w it while running.

Broad Street? If so, it's a fun one. Good luck regardless of what run.

Yes, broad st. ran again today trying Underarmour record, pace on the watch didnt seem accurate at times, but over all was good. all though activity was WAAAAY off. didnt seem like it tracked me, but says i worked out for 21 minutes.

Haven't been among the lucky to have gotten my Apple Watch yet. However, I've never found the phone GPS to be nearly as accurate as my Garmin 620. As the Watch uses the phone's GPS, I would expect it to be only as accurate as the phone. Only time will tell if I think I can trust it for serious training.

Enjoy the race.

I have had the exact same issue. I've now done five runs or walks with my watch, my phone with me, and each time the distance results have been between 2% and 10% below my tom-tom GPS watch and the run keeper app that was also running off my phone's GPS. It seems like it is getting slightly better each time, but I cannot figure out why there would be any difference at all when compared to another app using the exact same GPS. I'm in conversations with tech-support, and they are supposed to get back to me tomorrow with a response. If they have a fix, I will be sure to post it here.

dbwass wrote:

I'm still on the fence about this watch. It's a super sleek piece and a beautiful accessory, but I'm just not sure if it suits my purposes as a running watch. I still have a week to decide if I keep it or return it and try the new Garmin Vivoactive watch.

You should check out DC Rainmaker's review of the Vivoactive. His a triathlete and serious gadget guy.

dcrainmaker.com