Result
Result reflects the current submitted inputs.
- Risk A
- Reviewed 2026-05-26
- 2 sources
- Leg A and Leg B are perpendicular.
- Both legs use the same linear unit.
- Angles are returned in degrees.
- Intermediate values are not rounded.
Accuracy notes
- Risk level
- A
- Reviewed
- 2026-05-26
- Sources
- 2
- Primary result
- Hypotenuse
Formula logic is kept in a pure calculator module with fixtures, source notes, and page-visible assumptions.
What the result means
Use Hypotenuse as the headline answer for right triangle. The side opposite the right angle. Read the main measurement first, then verify whether secondary outputs use the same unit basis. Use area, perimeter, and angle opposite leg A to explain why hypotenuse moved when an input changed. Write the unit beside the result so area, volume, and linear measurements are not confused. Check unit consistency, diameter versus radius, squared or cubed units, and rounding precision before treating the result as final.
Use the result this way
- Start with Hypotenuse, then use supporting outputs only to explain the primary answer.
- Verify leg A and leg B before copying the result.
- Keep units consistent with the labels shown in the form and stay within the documented minimum and maximum ranges.
- Write the unit beside the result so area, volume, and linear measurements are not confused.
User job
How to use this calculator
Use Right Triangle Calculator when you need hypotenuse, then use area and perimeter to check the context for quick number work, classwork, spreadsheet checks, and explaining a calculation to someone else.
Best for
- Checking the core numeric relationship
- Comparing the main result with supporting outputs
- Reviewing a default example before entering your own leg a and leg b.
Check before relying
- Confirm sign, decimal, percent, and rounding assumptions before copying the number.
- Leg A and Leg B are perpendicular.
- Both legs use the same linear unit.
- Source context: Wikipedia, reviewed 2026-05-26.
Next useful step
- Pythagorean Theorem CalculatorUse next when the measurement task needs missing side instead of hypotenuse.
- Triangle CalculatorUse next when the measurement task needs area instead of hypotenuse.
- Area CalculatorUse next when the measurement task needs area instead of hypotenuse.
Formula
hypotenuse = sqrt(legA^2 + legB^2); area = legA x legB / 2; perimeter = legA + legB + hypotenuse. Key assumptions: Leg A and Leg B are perpendicular. Both legs use the same linear unit. Angles are returned in degrees.
- hypotenuse = sqrt(legA^2 + legB^2); area = legA x legB / 2; perimeter = legA + legB + hypotenuse.
- Leg A and Leg B are perpendicular.
- Both legs use the same linear unit.
- Primary source context: Wikipedia.
Inputs
Enter leg A and leg B for number checks, homework, spreadsheet review, and quick comparisons. Before calculating, keep units consistent with the labels shown in the form and stay within the documented minimum and maximum ranges. Leg A: Enter one positive perpendicular leg. Leg B: Enter the other positive perpendicular leg in the same unit.
Example
Using the default inputs, Right Triangle Calculator returns hypotenuse of 5 units. Adjust leg A and leg B to match your own scenario.
FAQ
How is hypotenuse calculated here?
hypotenuse = sqrt(legA^2 + legB^2); area = legA x legB / 2; perimeter = legA + legB + hypotenuse. The first assumption to check is: Leg A and Leg B are perpendicular.
What does Hypotenuse mean for right triangle?
Read the main measurement first, then verify whether secondary outputs use the same unit basis. Secondary values such as area, perimeter, and angle opposite leg A are there to explain the primary answer, not to replace it.
What should I enter for Leg A?
Enter one positive perpendicular leg. Use units for this field. Keep units consistent with the labels shown in the form and stay within the documented minimum and maximum ranges.
How does Leg B change hypotenuse?
Enter the other positive perpendicular leg in the same unit. Changing it can alter hypotenuse because the formula uses the submitted inputs together. Also compare unit consistency, diameter versus radius, squared or cubed units, and rounding precision.
Why does the right triangle example show 5 units for hypotenuse?
The default inputs produce 5 units for hypotenuse. Treat that as a format and scale check, then replace every default value with your own inputs.
Why does rounding matter for hypotenuse?
Rounding affects the displayed answer and can compound if you reuse the number. Keep more precision for intermediate work when the next step depends on it.
Sources
Last reviewed: 2026-05-26
- Reviewed 2026-05-26Pythagorean theoremWikipedia. Hypotenuse formula for right triangles.
- Scope
- General geometry reference for the relationship between right-triangle legs and hypotenuse.
- Supports
- Hypotenuse formula for right triangles.
- Reviewed 2026-05-26Trigonometric functionsWikipedia. Acute angle formulas using arctangent ratios.
- Scope
- General mathematics reference for tangent and inverse tangent relationships in right triangles.
- Supports
- Acute angle formulas using arctangent ratios.