DeskTray

Bubble Level

Check whether a surface is level or a frame is straight, using your phone’s motion sensor. Lay it flat for surfaces, or stand it on an edge for shelves, walls and pictures.

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Press Start, then place your phone on the surface

Lay the phone flat to level a surface, or stand it on its long or short edge against a shelf, frame or wall to check horizontal and vertical lines. Phone cases with a camera bump tilt the phone, so calibrate on a surface you know is level, or take the case off.

How to use Bubble Level

  1. Open this page on your phone and press Start level (on iPhone, tap Allow).
  2. Lay the phone flat on the surface, or stand it on its edge against the object.
  3. Adjust until the bubble is centred and turns green. Use Hold to freeze the reading.

Features

  • Surface (flat) and edge modes
  • Degrees and percent slope
  • Calibrate and hold reading
  • Vibrates when level

Frequently asked questions

How accurate is a phone bubble level?

Usually within about 0.5° after calibration, which is enough for shelves, frames, furniture and appliances. For construction work, check with a proper spirit level.

How do I calibrate it?

Place the phone on a surface you know is level and press Calibrate. A camera bump or case can tilt the phone, so calibrate with the case you will use.

What does the percent slope mean?

It is the rise over the run: 1% means 1 cm of height change over 1 metre. Drainage slopes for bathrooms and terraces are often 1–2%.

Does it work on a laptop?

Most laptops have no motion sensor, so use a phone or tablet.

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