Area and Volume Formulas Made Simple
The essential area, perimeter and volume formulas for circles, rectangles, triangles, spheres and cylinders — what they mean, how to handle composite shapes, and how to keep units straight.
Square Calculator
Verified formula Updated Jun 2026 Private — runs on your device
Verified formula
Private
Area
25.00
- Perimeter
- 20.00
- Diagonal
- 7.0711
For general information only — not financial, tax, legal or medical advice. Verify before you rely on it.
How to use the Square Calculator
The Square Calculator works out your area, along with 2 related figures in an instant. Enter side length and the result updates as you type — it is free, needs no sign-up, and runs entirely in your browser so your figures stay private.
- Enter the side length.
- Read off your area, together with perimeter and diagonal — the calculator updates automatically, with no button to press.
Formula
The Square Calculator uses the formula:
Area = Side length ^ 2
Worked example
For example, with side length of 5 units, the area is 25.00.
| Side length | 5 units |
|---|
| Area | 25.00 |
|---|---|
| Perimeter | 20.00 |
| Diagonal | 7.0711 |
Results are estimates for educational use, not professional advice.
Key terms explained
- Perimeter
- The total distance around the outside of a two-dimensional shape.
- Area
- The amount of two-dimensional space a shape covers, measured in square units.
Frequently asked questions
Square the side length: A = s². A square with a side of 5 has an area of 25 square units.
Multiply the side length by 4, since all four sides are equal: P = 4s. A side of 5 gives a perimeter of 20 units.
The diagonal equals the side times the square root of 2 (about 1.4142): d = s√2. For a side of 5 it is about 7.07 units.
Yes. A square is a rectangle whose length and width are equal, so all rectangle formulas apply to it.
The Square Calculator uses the formula: Area = Side length ^ 2. For example, with side length of 5 units, the area is 25.00.
Enter the side length. Read off your area, together with perimeter and diagonal — the calculator updates automatically, with no button to press.
Related guides
Square Table: Area by Side length
Reference table of area for Square across a range of side length values — exact, engine-computed figures you can read off at a glance.
How to Calculate Square: Formula, Steps & Examples
Learn how to calculate Square — the formula explained step by step, with worked examples and a free calculator to check your answer.