Learn
Tutorials
First time here? Start withhow to use the online protractor— load a file, click three points, read ±. The guides below are for one job each. Everything shown is free, with no account and no upload.
Measure angles in photos
Use this guide when the angle is on a photograph — phone snapshot, worksheet photo, or diagram scan — and you need to place the vertex on the subject, not a shadow.
Measure on PDF pages
Use this guide when the drawing is a PDF: page stepper, measurements that stay on one page, and zooming on thin CAD or worksheet lines.
Scale calibration for real lengths
Use this guide when you need millimetres, inches, or feet. Angles never need a scale; lengths do, and only on one plane.
Export for homework and reports
Use this guide when you need a hand-in: PNG vs SVG vs CSV vs a print-ready report, all unwatermarked.