How to Use the Online Compass

The online compass reads your phone's built-in magnetometer through the browser — no app needed. Here is how to start it, calibrate it, and get a heading you can actually trust.

Troubleshooting

Related: the compass corrects for magnetic declination automatically — hikers matching a paper map should know their map's declination date, since it drifts a little every year.

Step by step

  1. Open the compass page on your phone (compasses need motion sensors, so desktops show a demo dial only).
  2. Tap Start compass. On iPhone, approve the Motion & Orientation prompt; on Android it starts immediately.
  3. Hold the phone flat like a map, screen up, away from magnets — cases with magnetic clasps, car mounts and laptops all bend the reading.
  4. Calibrate by waving the phone in a slow figure-8 for a few seconds until the needle settles.
  5. Optionally allow location so the dial corrects from magnetic to true north using your local declination.
  6. Tap Focus mode for a clean, full-screen dial — Esc or the button exits.
Try it now
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—° Point your phone

Works offline · nothing leaves your device · magnetic → true north corrected with your local declination when location is allowed.