How to use this tool
- 1Lay the phone flat on the surface you want to check.
- 2If your browser asks, allow access to the motion sensor.
- 3Read the tilt in degrees and watch the bubble move toward the center.
- 4Tap Calibrate on a surface you trust to be flat to set it as zero.
About this test
This tool uses the phone's orientation sensors (accelerometer) to measure tilt front-to-back and left-to-right, showing a bubble that centers when the surface is level. It is handy for hanging a shelf, leveling a washing machine or checking a table without a physical level.
Calibration lets you zero the reading against a reference you trust, which also corrects for a phone that reports a small resting offset. Everything runs in your browser and no sensor data leaves your device.
Privacy: this tool runs entirely in your browser. No image, audio or device data is recorded or sent to any server.
Frequently asked questions
How accurate is a phone bubble level?
Good enough for everyday tasks, usually within a degree or two. For fine carpentry or masonry, a calibrated physical level is still more reliable.
The level seems off. What can I do?
Place the phone on a surface you know is flat and tap Calibrate. That sets the current position as zero and removes any resting offset.