About GeometryForge Play
How it works
GeometryForge is geometry you build with your hands, not just read about.
- Geometry Studio — rotate an arm to make an angle to an exact target, choose the polygon whose interior angles add to a given sum, and set the partner of a complementary or supplementary pair.
- Transformation Lab — slide, flip, turn, and scale shapes on a coordinate grid: name which transformation was used, tap where a vertex lands, and find a shape’s line of symmetry with a mirror line.
- Geoboard — stretch a rubber band around the pegs to enclose an exact area. As you drag, Pick’s Theorem (A = I + B/2 − 1) is recomputed so you can see why the area comes out the way it does.
- Concept kits — 17 short question rounds, from points & angles up to advanced synthesis.
Our privacy promise
GeometryForge Play is free, works offline, and collects nothing. No accounts, no ads, no tracking, and no data ever leaves your device — your progress, level, and streak are saved only in this browser.
Mistakes are part of it
You never lose anything for a wrong try. Wrong answers get a gentle explanation, and hints teach you how to think it through — not just the answer.