utility

Pocket Level

Turn a phone into a browser-based level and inclinometer using its orientation sensor.

Local processing

About your filesFiles and content selected in this tool are processed in your browser and are not uploaded to a Browser Kitty backend.

Operation demo See the basic workflow in a short video.

About this tool

Pocket Level uses a phone's orientation sensor as a browser-based level and inclinometer. Plane mode measures two axes, while edge/plumb mode focuses on a single axis for shelves, walls, and similar surfaces.

Along with a bubble-style view, it provides slope percentage, stability, a two-second average, zeroing, and a 180-degree two-point calibration workflow. Sensor readings stay on the device.

Good for

Quickly check whether a shelf or desk is level
Check plumb or inclination of a wall, post, or furniture using only a phone
Use a level from an HTTPS browser without installing a dedicated app

What it can do

Key capabilities available in this tool.

Level and plumb measurement
Angle and slope percentage
Zeroing and two-point calibration
Stability and 2-second average

How to use

Open the tool on a phone and tap Start measurement.
Grant motion/orientation sensor permission if the browser asks.
Choose Plane for flat surfaces or Edge/Plumb for shelves, walls, and similar edges.
Use zeroing, two-second average, hold, or 180-degree two-point calibration when needed.
Adjust the object while watching angle, slope percentage, bubble, and stability.

Supported

Sensors: uses Device Orientation/Motion-style browser APIs.
Display: X/Y angles, combined tilt, slope percentage, bubble, and stability.
Helpers: zeroing, hold, two-second average, and 180-degree two-point calibration.
Environment: sensor permission and Secure Context requirements depend on device/browser.

Limitations and notes

Accuracy depends on the device sensor, case, camera bump, and how the phone contacts the surface.
Some browsers do not expose sensors to file:// pages and require HTTPS.
Sound, vibration, and Wake Lock depend on device and browser support.
It is not a calibrated construction or surveying instrument; use dedicated equipment when certified accuracy is required.

Frequently asked questions

Can I use it on a PC?

The page can open, but the primary use is on phones with orientation sensors. Devices without suitable sensors cannot measure tilt.

Are sensor readings transmitted?

No. Measurement, averaging, calibration, and display run locally; sensor readings are not sent to Browser Kitty.

What if zero degrees seems off?

Use zeroing to treat the current surface as the reference. A 180-degree two-point calibration can also estimate a consistent device bias.

Can it replace a professional level?

It is intended for convenient checks. Use calibrated professional equipment for construction or surveying work that requires guaranteed accuracy.

Offline version and source code

The app can be saved as a single HTML file, but some browsers block sensors on file:// pages. Use an HTTPS host such as Browser Kitty when local sensor access is unavailable.

View source on GitHub