Formula Library
Every formula, made memorable
69+ school formulas with colorful cards, clear examples, and quick practice links.
Geometry
Area, perimeter, volume, and shapes.
19 formulasAlgebra
Equations, identities, and exponents.
14 formulasArithmetic
Percent, ratios, averages, and basics.
7 formulasTrigonometry
sin, cos, tan and triangle rules.
7 formulasCircles
π, radius, circumference, and chords.
6 formulasStatistics & Probability
Mean, median, mode, and chance.
7 formulasSpeed & Motion
Handy school formulas for speed and distance.
3 formulasInterest & Money
Simple and compound interest.
6 formulasStart with Geometry
Area of a rectangle, circle (πr²), Pythagorean theorem — with worked numbers.
Open Geometry Area of Circle
Example
Area of Circle
A = πr²
- Radius = 7
- Area ≈ 153.94