An area of a triangle calculator finds how much space a triangle covers using whatever measurements you have: base and height, all three sides, or two sides and the angle between them. It’s perfect for geometry homework, construction, gardening and crafts.
The most common formula is area = (base × height) ÷ 2, where the height is perpendicular to the base. A triangle with a base of 10 cm and a height of 6 cm has an area of 30 cm². If you know all three sides, use Heron’s formula: first find the semi-perimeter s = (a + b + c) ÷ 2, then area = √(s(s − a)(s − b)(s − c)). For sides 5, 6 and 7, s = 9 and area = √(9 × 4 × 3 × 2) = √216 ≈ 14.7.
If you know two sides and the included angle, use area = (1/2) × a × b × sin(C). For sides of 8 and 11 with a 30° angle between them, area = 0.5 × 8 × 11 × 0.5 = 22. For a right triangle, the two legs are the base and height, so area = (leg₁ × leg₂) ÷ 2.
Common mistakes: using a slanted side instead of the perpendicular height, forgetting to divide by 2 and mixing units. Remember that area is in square units. For real projects, like roof gables or garden beds, measure carefully and add extra material for waste.
How to use the Area of a Triangle Calculator on Minedit: enter your values in the fields, press calculate, and review the step-by-step breakdown under the result. If something looks off, change one input at a time to see how it affects the answer, which is also a great way to learn the math behind it.
Learn more on Wikipedia’s triangle article. Find trapezoid area, volume of a cone and square footage calculators on Minedit.