Triangle Square Footage Calculator
By Vinod Kondeti · Updated
Triangles come up in gable walls, corner garden beds and angled lot lines. The area is half the base times the perpendicular height. The height is measured straight up from the base, not along the sloped side.
How do I measure for a triangle project?
- For a right triangle, the two sides that meet at the square corner are the base and the height.
- For a gable end, the base is the wall width and the height runs from the top of the wall to the peak.
- Split any odd polygon into triangles and rectangles, then add them up.
How is the triangle amount calculated?
- Rectangle: length × width
- Circle: π × (diameter ÷ 2)²
- Triangle: ½ × base × height
- Square yards = ft² ÷ 9; m² = ft² × 0.09290304; acres = ft² ÷ 43,560
- Cost = ft² × your price per ft² (flooring: boxes × price per box)
Triangle calculator questions
What is the area of a triangle 10 ft wide and 8 ft tall?
½ × 10 × 8 = 40 ft².
Can I use the slanted side as the height?
No. Using a sloped edge overstates the area. Measure square to the base.
Sources
Estimates only. Use the coverage or bag size printed on your product. Read the square footage guide for worked examples.