Diagonal of Square Table: Diagonal by Side length
Reference table of diagonal for Diagonal of Square across a range of side length values — exact, engine-computed figures you can read off at a glance.
Diagonal of Square Calculator
Verified formula Updated Jun 2026 Private — runs on your device
Verified formula
Private
Diagonal
7.071068
For general information only — not financial, tax, legal or medical advice. Verify before you rely on it.
How to use the Diagonal of Square Calculator
The Diagonal of Square Calculator works out your diagonal 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 diagonal — the calculator updates automatically, with no button to press.
Formula
The Diagonal of Square Calculator uses the formula:
Diagonal = Side length × √(2)
Worked example
For example, with side length of 5, the diagonal is 7.071068.
| Side length | 5 |
|---|
| Diagonal | 7.071068 |
|---|
Results are estimates for educational use, not professional advice.
Frequently asked questions
Multiply the side by the square root of 2. A side of 5 gives a diagonal of about 7.07.
The diagonal splits the square into two right triangles with equal legs, so it is side × √2 by the Pythagorean theorem.
Divide the diagonal by √2, or multiply by about 0.7071.
Yes, always. It is about 1.414 times the side length for any square.
The Diagonal of Square Calculator uses the formula: Diagonal = Side length × √(2). For example, with side length of 5, the diagonal is 7.071068.
Enter the side length. Read off your diagonal — the calculator updates automatically, with no button to press.
Related guides
How to Calculate Diagonal of Square: Formula, Steps & Examples
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