Math practice · reimagined
Geometry
Turn Geometry into a fight you actually want to win. Every problem is an attack — solve it faster than your opponent and you land the hit.
Ages 4–99+ · no download · plays in your browser · 23 languages
How it works
Geometry
Pick a fighter, choose Geometry, and trust your numbers. The faster and cleaner you solve, the harder you hit — from gentle early grades all the way to Olympic-level challenges.
The perimeter is the distance all the way AROUND a shape — like walking the fence around a garden.
For a rectangle, add up all four sides. A 5 by 3 rectangle has sides 5, 3, 5, 3, so the perimeter is 5 + 3 + 5 + 3 = 16. (A shortcut: add length and width, then double.)
Type the total distance around.
Every level of Geometry
- T1PerimeterGrade 3 · 8 yrsPerimeter of a rectangle.Play free ▸
- T2AreaGrade 3 · 8 yrsArea of a rectangle.Play free ▸
- T3Triangle areaGrade 6 · 11 yrs½ × base × height.Play free ▸
- T4Angle sumGrade 10 · 15 yrsInterior angles of a polygon.Play free ▸
- T5Third angleGrade 10 · 15 yrsTwo angles given, find the third.Play free ▸
- T6Inscribed angleGrade 10 · 15 yrsCentral angle given, find the inscribed.Play free ▸
- T7Surface areaGrade 10 · 15 yrsSurface area of a box.Play free ▸
- T8Additive anglesGrade 4 · 9 yrsAn angle is split into two parts — find the missing part.Play free ▸
- T9Volume of a boxGrade 5 · 10 yrsl × w × hPlay free ▸
- T10CircumferenceGrade 7 · 12 yrsC = π × d ≈ 3dPlay free ▸
- T11Circle areaGrade 7 · 12 yrsA = π × r² ≈ 3r²Play free ▸
- T12Volume of a cylinderGrade 8 · 13 yrsV = π × r² × h ≈ 3r²hPlay free ▸
- T13Volume of a coneGrade 8 · 13 yrsV = ⅓πr²h ≈ r²hPlay free ▸
- T14Distance formulaGrade 8 · 13 yrs√((x₂−x₁)² + (y₂−y₁)²)Play free ▸
- T15Similar trianglesGrade 10 · 15 yrsCorresponding sides are proportionalPlay free ▸
- T16Arc lengthGrade 10 · 15 yrs(θ/360) × 2πr ≈ θr/60Play free ▸
- T17MidpointGrade 10 · 15 yrs(x₁ + x₂) / 2Play free ▸
- T18Circle equationGrade 11 · 16 yrs(x−h)²+(y−k)²=r²Play free ▸
- T19Angle relationshipsGrade 7 · 12 yrsAngles that fill a right angle, a line or a full turn.Play free ▸
- T20Volume of a sphereGrade 8 · 13 yrsV = 4/3 πr³ ≈ 4r³Play free ▸
- T21Special right trianglesGrade 10 · 15 yrs30-60-90: the short side is half the hypotenuse.Play free ▸
- T22Similar areasGrade 10 · 15 yrsSides scale by k, areas by k × k.Play free ▸
- T23Perpendicular slopeGrade 10 · 15 yrsThe negative reciprocal of the line's slope.Play free ▸
More math to master
— Quick answers —
Geometry: the short FAQ
- Is Geometry free to play?
- Yes. Geometry is free to play right in your browser — the whole curriculum, no download, no signup. Paid plans later unlock the full fighter roster, every stage and saved progress.
- Who is Geometry for?
- Anyone from 4 to 99+. The early grades stay gentle for beginners, while the higher tiers will make even the confident sweat.
- Do I need to download anything to play Geometry?
- Nope. Geometry runs in any browser, on a laptop, tablet or phone.
- Can Geometry be used in the classroom?
- Absolutely. Teachers run Geometry with a whole class and track who's improving — see the schools plan for per-student pricing and a teacher dashboard.