Practical tools for measured work
Bubble level with manual and sensor modes
Check two-axis relative tilt with opt-in device sensors, zero calibration and a manual angle fallback.
A physical bubble level shows tilt relative to gravity. This digital version can use your device’s orientation sensor, or illustrate two manually entered angles. Lay the device face up, in its natural portrait orientation, near horizontal.
Manual angle mode
Zero only on a known level surface. Otherwise the display measures change from that surface, not true horizontal. Switching input modes clears calibration.
Both displayed angles are within 0.2° of the chosen zero.
How it works
Sensor access starts only after you press the enable button. Supporting browsers may ask permission; HTTPS is required. If permission is denied, the API is unsupported or no data arrives within five seconds, use manual angles. Readings stay in this page and are not uploaded or stored.
Beta is front-to-back tilt and gamma is left-to-right tilt in the device’s natural orientation. The display subtracts each zero offset. The graphic stops moving at 10° per axis; numeric angles remain visible. The green threshold of 0.2° is a display setting, not a certified accuracy.
Reference: W3C device orientationLimitations
Sensor support and accuracy vary by device, browser, case and camera bump. Manual values illustrate supplied angles and do not measure your desk. Keep the device face up; this is not an edge-level or plumb mode. Verify against a physical spirit level before using measurements. It is a generic browser tool, not Google’s bubble-level app.
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