Pythagorean Theorem Calculator

What this calculator does

Most math & education tools bury the answer under ads and jargon. The pythagorean theorem calculator shows the number first, the breakdown next, and the assumptions in plain language.

For right triangles: a² + b² = c².

Formula and worked example are shown in plain language below.

Purpose-built for a specific decision — not a generic template.

Result updates live as you type — no "Calculate" button needed.

Includes a copy-ready summary and printable PDF view.

How to use the Pythagorean Theorem Calculator

Enter your values in the fields on the left.
Results update automatically.
Use action buttons to copy, share or print.

The formula

c = √(a² + b²)

Worked example

3² + 4² = 25 → c = 5.

Common mistakes

Only works for right triangles
Confusing legs and hypotenuse
Forgetting square root

When to use it

Use for geometry, distances, construction.

Pro tips for the Pythagorean Theorem Calculator

Bookmark this page: the URL and inputs are all you need to reproduce the exact result later.
Save your favorite scenarios by clicking the star icon — they're stored locally, no account needed.
For big decisions, run best-case, expected, and worst-case scenarios and compare the breakdowns side by side.

Frequently asked questions

›3D version?

d = √(a² + b² + c²).

›Find a leg?

a = √(c² − b²).

›Pythagorean triples?

3-4-5, 5-12-13, 8-15-17.

›Non-right triangles?

Law of cosines.

›Proof?

Many — Euclid's is classic.

›Can I embed the Pythagorean Theorem Calculator on my site?

Embedding isn't public yet, but you can link directly to this page — the URL is stable and shareable.

›Where does the formula come from?

The formula shown in the "How it works" section is the same one you'll find in standard math & education references — no proprietary tweaks or hidden weightings.

Embed this calculator

Drop the Pythagorean Theorem Calculator into your own site or blog post. Free to use — a small “Powered by CalcPilot” link is appreciated.

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