How to measure an angle on Android

On Android, the most reliable workflow is: screenshot → upload into the tool → align → measure → export.

Take a sharp screenshot

Open the tool and upload

Align a baseline using the grid

When this helps

Use this for angles in screenshots from apps, web pages, videos, CAD viewers, or PDF diagrams. A sharp, high-resolution capture improves stability.

1
Take a sharp screenshot
Capture the screen and crop to the angle area. Include a little extra on each side for easier alignment.
2
Open the tool and upload
Open the online protractor in your browser, tap upload, and select the screenshot from Photos/Gallery or Files.
3
Align a baseline using the grid
Rotate/flip and use the grid until one side direction is straight and consistent.
4
Place the vertex and pick 180°/360°
Move the center to the vertex. Use 180° for interior angles; switch to 360° for reflex angles (>180°).
5
Export once it matches
Sanity-check the reading by re-aligning and re-placing the vertex if needed. Export PNG/PDF when it’s correct.

Use a larger screenshot: zoom before capture when edges are thin or low-contrast.
Avoid perspective distortion (camera angle) when measuring photos of real objects—choose a frame that looks as flat as possible.
For fine tuning, switch snap mode or turn snap off for the last 1–2 degrees.