Running blind? So is your treadmill.

Your treadmill said 5 miles. You ran 4.

Treadwell measures your treadmill's actual belt speed with your phone, so you finally know your true pace and distance. The display shows the number it was told to hit. Your watch has no GPS indoors. Only Treadwell reads the belt itself.

See how it works

Free to download. iPhone Pro or Pro Max with LiDAR required.

Why your miles come up short

You followed the treadmill. You came up short.

Set the treadmill for 5 miles, trust it, and you might really run 4. The treadmill never measures its own belt. It shows the speed it was set to, but a worn or slipping belt runs slower than that. You did not slack. Your machine did, and it short-changed your workout without you ever knowing. Treadwell measures the belt itself, so the miles you log are the miles you ran.

Get Treadwell free

Treadmill, your target5.0 mi

Your Apple Watch4.8 mi

What you actually ran4.0 mi

A full mile short. You set out for 5 and ran 4. Your watch never caught it, and your workout never counted it.

Treadmills drift, wear, and slip, so the number on the screen is rarely the real one. Treadwell reads the belt itself and tells you the truth, whether your treadmill runs fast or slow.

How it works

Point. Hold. Know.

Hold your phone over the belt

Step to the side and hold your phone steady over the running belt for a few seconds. Never stand on a moving belt to hold your phone.

Treadwell measures the belt

The camera and the LiDAR sensor track the belt surface and work out how fast it is really moving.

Get your true pace and distance

Read your real pace in minutes per mile, not the treadmill's mph guess.

Why nothing else has solved this. The display shows only the speed it was set to. A watch has no GPS indoors. A footpod copies the calibration of the machine it runs on. Treadwell skips all of that and reads the belt itself with your phone's camera and LiDAR, the way a mechanic puts a meter on the engine instead of trusting the dashboard.

Measure once, then forget it. Calibrate a treadmill once and Treadwell learns that machine, so it can tell you the true speed for any setting, or what to dial in to hit a target pace.

Who it's for

If your treadmill numbers have ever felt off, they were.

You train by pace and zones

You run real workouts indoors and need your tempo to actually be tempo. Treadwell makes your indoor pace trustworthy, so your training log and your zones finally mean something.

Your watch miles never add up

You finish a run and the watch logged less than you ran. Recalibrating did nothing. Treadwell measures the belt, so your miles are real.

You think in pace, the treadmill shows mph

A treadmill speaks a car's language, miles per hour. Treadwell gives you your pace the way you actually train, in min/mi or min/km, and tells you the speed to set to hit it.

Your wearable is guessing indoors

Apple, Garmin, whatever you wear, indoors it has no GPS, so it guesses. Calibrate your treadmill once, then pick the pace you want and Treadwell tells you the exact speed to set. From there it tracks your true distance and pace live for the whole run. More precise than the wrist, and in the pace you actually train in.

Questions

The questions runners ask before downloading.

Indoors, neither device is measuring your belt. A watch has no GPS, so it estimates from your arm swing. A footpod needs calibration on each treadmill and can drift on home machines. The display only shows the speed it was set to. Treadwell measures the belt surface itself, so you find out what you really ran, whatever the treadmill or the watch said.

No. Measure once, or calibrate a treadmill once, and Treadwell remembers that machine. After that you just read the true speed for any setting.

In our own testing against a precision tachometer, Treadwell reads within about 2% of the true belt speed. For context, even a GPS running watch is only a few percent accurate outdoors. A study of eight popular running watches found their distance error ran from about 3% to 6%, and indoors a watch has no GPS at all, so it is only estimating. Treadwell is as trustworthy as the watch you already rely on, and it is the only one that actually measures your treadmill.

Any iPhone Pro or Pro Max with LiDAR, iPhone 12 Pro or newer. The newest Pro models give the best results at faster running speeds.

Treadwell is free to download. Measure your treadmill and see the real gap for free. A one-time upgrade unlocks the full toolkit: per-treadmill calibration with speed predictions, live workout tracking, and your run history.

Treadwell is live on the App Store. Download it, walk up to your treadmill, and you will know your true speed in under a minute.

Nothing. Treadwell does not collect your data. Your measurements and runs stay on your phone.

Want the longer answers?Our guides cover treadmill accuracy in depth, including how to check whether your machine is telling the truth.

Read the guides