Square Formulas
2D Shapes
Square
- Area
- A = a2
- Perimeter
- P = 4a
- Diagonal
- d = a√2
- a side length
Square formulas explained
A square has four equal sides and four right angles. Its diagonal splits it into two isosceles right triangles. Below are all the square formulas with what each letter means, a worked example and a free calculator.
- Area:
A = a² - Perimeter:
P = 4a - Diagonal:
d = a√2
Square calculator
Live calculator
Square calculator
Worked example: area of a square
Given Side a = 5 cm, substitute the values into each square formula:
- A = 5² = 25 cm²
- P = 4 × 5 = 20 cm
- d = 5 × √2 = 7.07 cm
Square Formula SheetFormulas, variables, a worked example and practice questions with answers.Download PDFOpen
Square formulas FAQ
What is the formula for the area of a square?
The area of a square is A = a², where a is the side length.
What is the formula for the perimeter of a square?
The perimeter of a square is P = 4a, where a is the side length.
What is the formula for the diagonal of a square?
The diagonal of a square is d = a√2, where a is the side length.
Can I download the square formulas as a PDF?
Yes. Use the Download PDF button on this page for a free printable square formula sheet with a worked example and practice questions.
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