About Us
How Smart Protractor stays accurate and private
Smart Protractor is a focused protractor tool for measuring angles on images, screenshots, and diagrams—fast, repeatable, and privacy-first.
What we provide
A browser-based protractor with 180°/360° modes, guides, snap, and exports (PNG/PDF + CSV/Excel/JSON) so you can share results and keep a record.
Accuracy principles
We optimize for repeatability: clear alignment tools (grid, snap, guides), predictable reading, and exportable data. The best results come from straight-on images and careful baseline alignment.
Privacy by design
Your images stay on your device. The tool works locally in your browser and does not upload or store what you measure.
How it works
Smart Protractor renders your image to a canvas, overlays protractors and guides, and computes angles from your points. Exports are generated locally from the canvas and measurement data.
Updates
We iterate based on real measurement workflows and troubleshooting feedback, and we adjust tutorials and copy when users get stuck.
What we don’t provide
No user accounts, no cloud storage, and no guarantees for safety-critical use. If you need certified measurement, use professional tools.
Feedback
Found a bug or a confusing edge case? Send a short description and a sample screenshot (if you’re comfortable) so we can reproduce it.