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📐 Geometry Angle Explorer

Drag the arm around the protractor to build any angle, see it classified live, and try snap-to-shape challenges.

📐 Drag anywhere on the dial below to build an angle between the two arms. The angle updates live, gets classified automatically, and you can try challenges to hit a specific type of angle.

How This Works
  1. Touch or click inside the circle and drag around it — the blue arm follows your finger or cursor.
  2. The gold arm stays fixed at 0°. The angle you're building is always measured between the fixed arm and the arm you're dragging.
  3. Watch the number and the badge. The degree reading updates instantly, and the badge below it tells you what type of angle you've made — Acute, Right, Obtuse, Straight, or Reflex.
  4. Try a challenge. Press "Start Challenges" and you'll be asked to build a specific type of angle. Get it in range, then press "Check Angle" to confirm.
Reminder: Acute is less than 90°, Right is exactly 90°, Obtuse is between 90° and 180°, Straight is exactly 180°, and Reflex is more than 180°.
0° Zero Angle
Drag inside the circle to build your first angle.