How to Calibrate GPS Distance
This guide explains step-by-step how to use the Speed Calibration Tool, measure a known distance (for example between mile markers or a measured bike track), and interpret the relative bias between GPS-measured distance and the known reference.
Procedure
- Find a measured stretch (100–1000 m) or use a known loop.
- Open the Speed Calibration Tool and start recording before you begin moving.
- Stop recording at the end of the stretch and enter the known distance into the tool.
- Review the relative bias and take notes about device placement and conditions.
Interpreting results
A relative bias under ±5% is expected for consumer devices; larger biases suggest hardware or placement issues.