GPS Elevation Correction
Fix bad GPS data with our integrated ground elevation database
Today we announce a new feature that has been a very popular request from our users:
If your watch or cycling computer gives you unreliable elevation data (either GPS or barometric), now you can fix it with one button click. We've also enabled an option to auto-correct data on new workouts. You can undo elevation correction (to revert to your recorded data), and you can even overlay the original recorded data with the corrected data on a chart to see where differences are. Interested? Read on.
Why is Elevation Correction Important?
As a runner or cyclist your key performance metrics are speed, distance and time. On the other hand your watch will also record changes in your altitude during your workout. You may not know, but these altitude changes are the basis of several calculations related to performance:
- Your total elevation gain and loss and related personal records.
- Your equivalent level pace (i.e. Grade Adjusted Pace).
- Auto-detection of hill climbs, and related metrics (e.g. Vertical Ascent Meters or VAM).
- Your effort (TRIMP) for speed-based workouts.
However, a problem arises: in some scenarios, elevation recorded from your device can be inaccurate. Inaccurate inputs means inaccurate calculations and inaccurate performance data. This is where elevation correction comes in. If your recorded elevation is bad, you can use our world-wide database of measured ground elevations to "fix" your elevation data and recalculate any related metrics.
Correcting Elevation for a Single Workout
To fix elevation for an existing workout, go to the workout details, click the "Edit" button and select "Correct Elevation"
After some time the page will refresh with your elevation data replaced by data from the ground elevation database. You may notice changes in the elevation gain/loss values, and other fields that have been recalculculated based on the new elevation data.
If you don't like the ground elevation data, you can revert the change by clicking the "Edit" button and selecting "Correct Elevation" to uncheck it.
No need to export your original workout file, or save a copy around like other websites - we do the work for you and make it as easy as a button click.
Viewing Corrected vs Recorded Data
On workouts where elevation has been corrected you can view the original recorded elevation data in the chart. This can be useful to compare the two and see what corrections were made. Select the Elevation (Recorded) option from the chart metric list, either as a single chart or overlay.
Enabling Auto-Correction for New Workouts
If you know your GPS device consistently gives you bad elevation data you can enable an option to turn on auto-correction for every new workout imported into your history. This option applies to workouts added through a sync feature (such as from Garmin Connect or Suunto Movescount), files imported on the website, and data added through our partner API (from services such as tapiriik or apps such as iSmoothRun).
To enable auto-correction for all new workouts go to the My Account > Preferences page:
As with workouts you've manually corrected we'll store your original recorded elevation data. This means you can revert the corrections at a later time with a button click.