Online Spirit Level

Online Spirit Level turns your phone into a bubble level using its built-in motion sensors. Lay your phone flat on a table, shelf, or floor to check whether the surface is level, or press it against a wall or column to automatically switch to vertical mode and check plumb. No app download is required — just open the page and start measuring.

Key Features

• Surface leveling: the bubble follows the tilt direction in real time; when it reaches the center, the surface is level.
• Vertical / plumb check: press the phone against a wall or frame and the tool automatically switches to vertical mode.
• Live angle readouts: shows left/right and front/back tilt angles plus the combined offset, accurate to 0.1°.
• Two bubble views: choose between a round dial and bar-style vials, mimicking a real spirit level.
• Zero calibration: set the current pose as the zero point for relative measurements, and reset it anytime.
• Reading lock: freeze the current reading when measuring in hard-to-see spots, then check the result after moving the phone away.
• Adjustable tolerance: level detection range can be set to ±0.5°, ±1°, or ±2°.
• Sound and vibration alerts: an optional beep (and vibration on supported phones) sounds when the bubble is centered.

Use Cases

• Hanging pictures, frames, and shelves straight.
• Leveling washing machines, fridges, desks, or pool tables.
• Quick reference checks during renovation and woodworking DIY.
• Verifying that walls, door frames, and columns are plumb.

How to Use

1. Tap "Start" and allow the page to access motion sensors when prompted.
2. Place your phone flat on the surface to test. When the bubble is centered and the status shows "Level", the surface is good.
3. To check plumb, press the edge of your phone against a wall or column — the tool switches to vertical mode automatically.
4. Use "Calibrate" to set the current pose as zero for relative measurements, and "Lock" to freeze a reading.

FAQ

Q: Is this spirit level free?

A: Yes, completely free. No registration or app installation is needed.

Q: Why does nothing happen after tapping Start?

A: Sensor permission is most likely blocked. Choose "Allow" in the prompt; if you previously denied it, re-enable motion and orientation access in your browser or system settings.

Q: Does it work on a desktop computer?

A: It requires a device with a gyroscope or accelerometer. Use a phone or tablet with Chrome, Safari, or Edge.

Q: Is it as accurate as a professional spirit level?

A: Phone sensors are accurate enough for everyday tasks like hanging pictures or leveling furniture. For precision construction work, please use professional instruments.

Q: Why is there no sound alert?

A: Make sure the "Level sound" switch is turned on and your phone is not in silent mode.