Choose a flat shape, enter positive dimensions in one length unit, then review its formula and area conversions.
01 / SHAPE & UNITS
02 / DIMENSIONS
Dimensions must be positive and in the same length unit. Triangle and parallelogram height must be perpendicular; ellipse inputs are radii.
03 / YOUR RESULT
04 / CALCULATION
8 × 5 = 40 m². Convert lengths to meters first, then square the unit conversion factor to calculate m² and other area units.
Geometry calculations stay in your browser. Illustrations are schematic, not to scale.
Enter the values you want to compare; processing happens in your browser.
Adjust optional settings and review validation feedback before relying on the estimate.
Review the formulas and equivalent values, then copy the result you need.
Select rectangle, square, triangle, circle, parallelogram, trapezoid or ellipse. Enter the required positive dimensions and length unit.
Seven shape-specific formulas, simple illustrations, numeric substitutions and m², cm², ft² and in² conversions.
All dimensions and area calculations remain in your browser. Illustrations are schematic, not to scale.
Rectangle, square, triangle, circle, parallelogram, trapezoid and ellipse are supported with shape-specific positive dimensions.
Use the perpendicular distance from base to the opposite point or parallel edge; a slanted side length is not the height.
Enter radius, which is half the diameter. Circle area is π times radius squared.
Trapezoid area equals the sum of the two parallel bases times perpendicular height divided by 2. Ellipse area is π times its two radii.
Convert each length to meters, square its conversion factor and use m² to derive cm², ft² and in².
Diagrams are simple not-to-scale illustrations. Measurements and calculations stay in your browser and are not uploaded.