Area Calculator
Calculate area for rectangles, circles, triangles, and trapezoids — no math required.
How to use
- Select the shape you want to calculate the area for.
- Enter the dimensions for that shape — width and height for a rectangle, radius for a circle, base and height for a triangle, or two parallel sides and height for a trapezoid.
- Click Calculate to see the area and the formula used.
When people use this
- Measuring floor space for furniture or carpet.
- Calculating land or garden plot area.
- Figuring out how much material is needed for a surface.
- Checking geometry homework or DIY project measurements.
Examples
Rectangle. A 10 ft × 6 ft rectangle has an area of 60 square feet.
Circle. A circle with a 5 ft radius has an area of about 78.54 square feet (π × 5²).
Triangle. A triangle with base 10 and height 6 has an area of 30 square units (½ × 10 × 6).
Trapezoid. A trapezoid with parallel sides 6 and 10 and height 4 has an area of 32 square units (½ × (6+10) × 4).
Frequently asked questions
What units does this use?
The calculator uses whatever units you enter — feet, meters, inches, etc. The result is in the same unit squared (sq ft, m², etc.). Just keep units consistent.
How do I measure a room's area?
Measure the length and width of the room and use the rectangle formula. For irregular rooms, break them into rectangles and add the areas.
Can I measure in feet and inches?
Enter length and height in the same unit. If you measured in feet and inches, convert the inches to a decimal of a foot — 12 ft 6 in becomes 12.5.