Online calculator. Triangle area. Heron's formula.

• enter the lengths of triangle sides;
• select units of measurement - meter (m), centimeter (cm) or millimeter (mm);
• select in which units you want to get the area - square meters (m²), square centimeters (cm²) or square millimeters (mm²).

You can input only integer numbers or fractions in this online calculator. More in-depth information read at these rules.

If you have any difficulties with units conversion, you can use the length converter and area converter.

Additional features of triangle area calculator using the Heron's formula

• Use and keys on keyboard to move between field in calculator.