Rewrite the manufacturer and device on a FIT file.

Three common reasons. First, a third-party recording app (RideWithGPS app, Wahoo Fitness, some Garmin Connect IQ data fields) wrote a generic or wrong device tag and you want the file to show your real head unit. Second, anonymising before sharing - the serial number can identify a specific device, which carries privacy implications when sharing publicly. Third, unifying activities across multiple head units (you ride a Wahoo on the road and a Garmin off-road but want everything to appear as one device on Strava).

It tries. Garmin Connect uses the file_id manufacturer + product + serial combination to identify which paired device an upload came from. If those three fields match a device on your account, the activity lands under that device. If they do not match (because you wrote a different serial), the activity lands as "Other Garmin device" or under a generic bucket. For clean re-attribution, set the serial to match the actual paired unit.

Use the device changer with the "Randomise serial" option enabled, which writes a random serial number that does not link to your actual device. Combine with our [GPX Privacy Stripper](/tools/gpx-privacy-stripper) to also trim the start and end of the activity (removing your home address) and scrub athlete-name metadata, and you have a fully anonymised file safe to share on a forum or route-aggregator site.

The dropdown includes all major manufacturers: Garmin (Edge 530/540/830/840/1030/1040/1050, Fenix 6/7/8, Forerunner 245/255/265/955/965, etc), Wahoo (ELEMNT BOLT/ROAM/RIVAL), Coros (Pace/Apex/Vertix), Polar (Vantage/Grit/Ignite), Suunto (Race/Vertical), Stages, Bryton, Lezyne. For exotic devices or vendor-specific enums not in the dropdown, use the free-text product field with the Garmin product ID.

Strava reads the manufacturer and product from the file_id message and displays them on the activity page. Re-upload the rewritten file (after deleting the original or shifting the start time with our [FIT Time Adjuster](/tools/fit-time-adjuster) to avoid duplicate detection) and the new device shows up. Strava does not validate that the device is one you actually own - if you write "Edge 1040" the activity will display as recorded on an Edge 1040.

No - only the manufacturer, product, and serial fields in the file_id and device_info messages are rewritten. The record stream (lat, lon, elevation, HR, power, cadence, speed, temperature, distance), laps, sessions, and event messages are untouched. Activity stats, route, and stream data are identical before and after the device change.

FIT files often have multiple device_info messages - one for the head unit and one each for paired sensors (HRM, power meter, cadence sensor). The tool only rewrites the device_info entry that matches the file_id (the recording device itself); paired sensor entries are left alone. This means HR-strap and power-meter metadata stays accurate while the head-unit identity changes.

Yes - free, no signup, no upload. The tool exists because changing the recorded device after the fact is something Garmin Connect, Strava, and every other platform refuses to let you do, even when the recorded device is wrong.