Free Online Protractor — Measure Angles with Your Phone
Tilt your phone to measure angles in real time. No app needed — works instantly in any browser.
Tilt your phone sideways to measure angles.
※ Some browsers may ask for sensor permission — tap "Allow" when prompted.
0.0°
※ This is an approximate angle meter suitable for everyday use.
For professional measurements (construction, engineering, medical), please use certified instruments.
How to Use
- Tilt your phone — the angle updates in real time.
- If permission is requested, tap "Allow" to enable the motion sensor.
- Hold flat on a surface for 0°, stand upright for 90°.
Common Uses
📐 Check if a shelf is level
🪵 DIY woodworking angles
🪟 Measure window or door tilt
🏗️ Roof pitch estimation
FAQ
- Q: Is this accurate enough for real use?
- A: For everyday tasks (checking level, rough angles) yes. For professional construction or engineering, use a certified tool.
- Q: Does it work on iPhone?
- A: Yes. Tap "Allow Sensor Access" if Safari asks for motion permission.
- Q: Do I need to install anything?
- A: No. This protractor works entirely in your browser — no download or installation needed.
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