The calculation, without hidden assumptions
Area is one search intent with several common formulas, so splitting every simple shape into another thin page creates more friction than value. This parent calculator asks only for the dimensions needed by the selected shape, converts the measurements through a consistent base unit and shows the formula with your numbers substituted. Dedicated Circle, Triangle and Rectangle calculators remain available when you need their extra geometry.
How to use this calculator
Choose the 2D shape and the unit used for the input dimensions.
Enter only the dimensions shown for that shape, then choose the square unit you want for the answer.
Check the converted result and open Show the working to verify the formula and substituted measurements.
Where people use it
- •Flooring, paint, tile and landscaping estimates
- •Fabrication and drawing checks
- •Geometry homework and formula verification
- •Converting a measured area into square feet, square metres, acres or hectares
Example: 12 ft × 9 ft rectangle
The base calculation is 12 × 9 = 108 ft². Choosing square metres converts the same physical area to about 10.0335 m²; the geometry is calculated before the output-unit conversion.
What the result does not assume
- •All dimensions for a shape must use the same selected input length unit.
- •Triangle and parallelogram height means the perpendicular height, not a sloping side.
- •Ellipse inputs are semi-major and semi-minor radii. A sector angle must be greater than 0° and no more than 360°.
- •Composite or irregular floor plans should be split into measurable sections and added rather than forced into an unrelated formula.
Frequently asked questions
What shapes does this Area Calculator support?+
Rectangle, square, triangle, circle, trapezoid, parallelogram, ellipse and circular sector.
Can I enter feet and get square metres?+
Yes. Choose feet as the input length unit and square metres as the output area unit. The calculator converts through square metres internally.
Why is area measured in square units?+
Area describes a two-dimensional surface, so scaling a length unit affects two dimensions. One metre by one metre is one square metre.
Should I use this or the Circle Calculator?+
Use this parent calculator when you are comparing shapes or converting area units. The dedicated Circle Calculator is better when you also need radius, diameter and circumference relationships.
Semantic next steps
Continue the calculation
These links move to a different input, formula or project stage rather than a keyword variation of this page.
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OpenMore in this calculator collection
Browse nearby calculators in the same topic cluster so related pages reinforce each other instead of sitting as isolated URLs.
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Give readers the live calculator without rebuilding the math. Copy the responsive embed in one click, or customize width, height, border and corner radius before publishing. The branded MAXScanner attribution stays visible.
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Keep the result connected to the real job
MAXScanner keeps the formula and assumptions beside the result so you can verify the number before using it in a drawing, estimate, specification, worksheet or document. Where a supplier, manufacturer, drawing or applicable standard owns a requirement, that source remains authoritative.