Geometry & measurement

Triangle area

Calculate triangle area from base and height or three sides.

LocalFree
Study & learning use only
Use the result as a learning aid and verify important calculations against your course material or instructor.
This tool runs on your device in the browser.
Instructions and limitations
TOOL GUIDE

What this tool is for

Triangle area — Calculate triangle area from base and height or three sides.

Useful for practice, understanding the method, and checking homework steps where outside tools are allowed.

Common uses
  • Practice a formula or method
  • Check your working
  • Review before a lesson or exam
Study and learning use only

Use the result for practice and understanding, not as a guaranteed answer. Verify important calculations and follow your school, university, and academic-integrity rules.

EXPLANATION & EXAMPLE

Understand the result—not just the number

Core ideaA=½bh or Heron

Use base-height when height is known; Heron’s formula works from three valid sides.

Quick exampleUse the starting values, then change one input to see its effect.

After calculating, the tool shows the values used and the working so you can check it.

Learn the method, step by step — in a new tab

Triangle area using base and perpendicular height

Menu