What does this tool do

The Compass tool combines a Device Compass and a Bearing Converter in one. The Device Compass uses your phone or tablet's magnetometer to show live heading (0–360° and cardinal direction). The Bearing Converter converts between degrees (0–360°) and 16 cardinal/intercardinal directions (N, NNE, NE, ENE, E, …). All runs in your browser; no server calls.

How to use it

Device Compass tab — Tap "Enable compass" to grant permission. On iOS, you must allow device orientation access. Hold your device flat; the needle and heading update in real time. Works best on phones and tablets; desktop usually lacks a magnetometer.
Bearing Converter tab — Choose "Degrees → Cardinal" to convert an angle (e.g. 45) to a direction (NE), or "Cardinal → Degrees" for the reverse. Enter a value or select a cardinal; the result appears instantly. Copy with one click.
Switch tabs — Move between Device Compass and Bearing Converter as needed.

How it works

Device Compass: Uses the browser's deviceorientation event. On Chrome for Android, the heading comes from alpha. On Safari for iOS, the tool uses webkitCompassHeading (available after DeviceOrientationEvent.requestPermission() is granted). A fixed compass rose shows N, E, S, W; the needle rotates with the heading. Requires HTTPS and a device with orientation sensors.

Bearing Converter: Maps degrees to 16 cardinal points using 22.5° slices. 0° = N, 22.5° = NNE, 45° = NE, 90° = E, and so on. Cardinal → Degrees returns the midpoint of each slice (e.g. NNE → 22.5°). Input is validated; maximum 20 characters to avoid performance issues.

All computation runs entirely in your browser. No data is sent to any server.

Use cases & examples

Outdoor navigation — Check which way you're facing when hiking or orienteering.
Maps & GIS — Convert bearing values between numeric and cardinal formats.
Marine & aviation — Translate heading reports (e.g. "heading 315°" → NW).
Education — Teach compass directions and angle-to-bearing conversion.

Examples

Degrees → Cardinal:

0 → N
45 → NE
90 → E
180 → S
315 → NW

Cardinal → Degrees:

N → 0°
NNE → 22.5°
NE → 45°
E → 90°
NW → 315°

Limitations & known constraints

Device Compass — Requires HTTPS. Desktop PCs typically lack magnetometer hardware; use the Bearing Converter tab instead. iOS 13+ requires explicit permission; the user must tap "Enable compass" to start. Some environments (e.g. iframes, restricted contexts) may block device orientation.
Bearing Converter — 16-point compass only (no 32-point). Input capped at 20 characters. Degrees outside 0–360 are normalized into that range.

Compass

ガイド