Online Protractor – Measure Angles Accurately

How to Use the Online Protractor

This virtual protractor lets you measure angles with precision directly on your screen. Follow these simple steps:

Click Point 1: Click anywhere on the canvas to mark the first arm of your angle
Click Point 2 (Vertex): Click the center point where the two lines meet
Click Point 3: Click the third point to complete the second arm
Read the angle: The measurement appears instantly in degrees

The angle is calculated mathematically, so you don't need to calibrate for your screen size. However, for measuring physical objects on screen, use our online ruler tool first.

Key Features

speed Instant Measurement

Get precise angle readings in real-time as you click points. No manual calculation needed.

360 0-360° Range

Measures any angle from 0 to 360 degrees with decimal precision.

devices Works Everywhere

Use on desktop, tablet, or smartphone. No installation required, browser-based.

refresh Easy Reset

Clear and start over with one click. Flip angles to measure reflex angles instantly.

Common Uses

Geometry homework: Verify angle calculations or measure drawn angles
Graphic design: Check rotation angles in mockups and layouts
Architecture: Measure roof pitches, corner angles in plans
Woodworking: Plan miter cuts and joint angles
Engineering: Verify technical drawing angles
Education: Teaching tool for demonstrating angle concepts

Angle Types Quick Reference

Acute angle: Less than 90° (sharp angle)
Right angle: Exactly 90° (square corner)
Obtuse angle: Between 90° and 180° (wide angle)
Straight angle: Exactly 180° (straight line)
Reflex angle: Between 180° and 360° (use flip button)

💡 Pro Tip: For measuring angles on physical objects, place them on your screen and use the protractor. For best accuracy, ensure your browser zoom is at 100% (Ctrl+0 or Cmd+0).

Why Use an Online Protractor?

Traditional physical protractors can be hard to read, easy to lose, and limited in size. Our digital protractor offers:

✅ Always available when you need it
✅ Perfect for digital design workflows
✅ No parallax error (viewing from wrong angle)
✅ Instant precise readings without estimation
✅ Can measure larger angles than physical protractors
✅ Free and accessible from any device

Related Tools: Online Ruler • Grid Paper Generator • Scale Converter • Unit Converter