Pythagorean Theorem Calculator
Right-triangle solver: find c from legs or a leg from the other leg and hypotenuse.
Limitation: Educational geometry for right triangles only.
How to Use the Pythagorean Theorem Calculator
Right-triangle solver: find c from legs or a leg from the other leg and hypotenuse.
Open the Pythagorean calculator and read field labels.
Match the mode
Educational geometry for right triangles only.
What It Calculates
Right-triangle solver: find c from legs or a leg from the other leg and hypotenuse.
Worked Examples
Legs 3 & 4
Inputs
Result
√(9+16) = 5.
Leg a from c=5, b=4
Inputs
Result
√(25−16) = 3.
Leg b from c=13, a=5
Inputs
Result
Classic 5-12-13 triple.
Check your mode
Educational geometry for right triangles only.
Frequently Asked Questions
Still have questions about this calculation?
Try the CalculatorFormulas
Standard definitions with assumptions noted below.
Formula
Scientific Background
Standard geometry definitions with assumptions stated on-page. Educational only—not professional certification.
Sources & review
Pythagorean Theorem Calculator documents the references behind its formulas and assumptions. Always treat results as educational estimates, not personalized professional advice.
Last reviewed
July 22, 2026
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