๐ฆArea Calculator
Pick a shape and enter its dimensions to calculate area, with the formula shown.
Runs entirely in your browser. No data is sent to a server.
Free Area Calculator
Calculate the area of any common shape with our free area calculator. Pick from triangles, rectangles, squares, circles, trapezoids, parallelograms, rhombuses, regular polygons, ellipses, and circular sectors โ enter the relevant dimensions, and get the area instantly with the exact formula shown, substituted with your values.
Triangles can be solved from base and height, or from all three sides using Heron's formula. Circles, sectors, and ellipses show results in exact ฯ-form as well as decimal. Regular polygons compute area correctly from either side length or apothem, using the proper trigonometric formula rather than an approximation.
Every input is validated for the shape you've picked, so impossible dimensions (like sides that can't form a triangle) are caught immediately. No sign-up, no downloads โ just pick your shape and calculate. See the About page or the FAQ for more.