Calculator Tools
Calculate the area of a rectangle, square, triangle, circle, trapezoid, parallelogram or ellipse. See the formula and convert the result between metric and imperial square units with squared conversion factors.
Formula
A = l × w
Simple workflow
How to use Area Calculator
- 1Choose a Shape, Dimension unit and Result unit.
- 2Enter the dimensions named by the displayed formula.
- 3Select Calculate area to see the substituted values and correctly converted square result.
Good to know
Frequently asked questions
Which shapes can I calculate?
This page supports rectangles, squares, triangles, circles, trapezoids, parallelograms and ellipses. It calculates one ideal shape at a time.
Why is one square metre 10,000 square centimetres?
One metre is 100 centimetres in both dimensions. Area therefore scales by 100 × 100, so 1 m² equals 10,000 cm².
What measurements does an ellipse need?
Enter the semi-major and semi-minor axes: the distances from the centre to the edge along the ellipse's two principal directions.
What happens when a dimension is zero?
A zero dimension produces zero area. Negative dimensions and missing, nonnumeric or infinite values are rejected.
Practical guide
Choose a shape, apply its formula and convert square units
Area measures a two-dimensional surface. Choose the shape and enter the dimensions named by its formula. UtilSprout converts every dimension to metres, calculates square metres, then converts the result to the selected square unit.
Area conversion uses a squared scale. One metre is 100 centimetres, so one square metre equals 100 × 100, or 10,000 square centimetres. A linear conversion factor by itself would produce the wrong area.
Worked example
Convert the area of a one-metre square
- Start with
- Square with side 1 metre.
- Choose
- Choose square centimetres for the result unit.
- You get
- A = a² gives 1 m², which equals 10,000 cm².
Tips for a useful result
- Use the displayed formula to confirm which dimensions the selected shape needs.
- Use the same dimension unit for every field in one calculation.
- A zero dimension produces zero area; a negative dimension is rejected.
Supported formulas and limitations
The calculator supports rectangles, squares, triangles, circles, trapezoids, parallelograms and ellipses. An ellipse uses its two semi-axis lengths, measured from the centre to the edge.
Results involving π are rounded for display. The formulas describe ideal shapes and do not account for irregular edges, measurement uncertainty or material thickness.
Dimensions and results remain in this browser and are not stored, placed in a URL or sent to analytics.
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