Protractor: Angle Measure

Protractor is the most accurate digital protractor, angle ruler, and angle finder for Android. Measure any angle from 0 to 360° using your phone's gyroscope and screen — no analog tool needed.

Whether you're a student doing geometry homework, a craftsman setting miter cuts, or a designer measuring drawings, Protractor turns your phone into a precision angle measurement tool.

▶ MAIN FEATURES

• Protractor — measure angles between two screen points

• Angle ruler — touch two points to read the angle

• Gyroscope mode — measure physical angle by rotating the phone

• Plumb mode — vertical reference angle

• Pitch & roll mode — independent X/Y axis angles

• 0.1° precision via accelerometer + gyroscope sensor fusion

• Hold mode locks the value hands-free

• Switch units: degrees, radians, gradians

• Dark mode for indoor use

• Works fully offline — no account, no ads block

▶ HOW TO USE

1. Open Protractor and choose mode: screen touch or gyroscope

2. For screen mode: tap two points on the half-circle scale

3. For gyroscope mode: rotate the phone to measure

4. Read the angle in degrees, radians, or gradians

▶ WHO USES PROTRACTOR

• Students learning geometry and trigonometry

• Math teachers demonstrating angles in class

• Carpenters setting miter and bevel cuts

• Tile installers checking corner angles

• Roof installers calculating pitch

• Architects and designers measuring drawings

• Sewing pattern makers angling darts

• Quilters cutting precise triangle angles

• Engineers verifying mechanical part angles

• Hobbyists building model planes and trains