Volume and Area Calculator

Choose a shape and enter dimensions in metres

Choose a rectangle, circle, triangle, rectangular prism or cylinder. Enter the displayed dimensions in metres; use radius rather than diameter for circles and cylinders. Area results are in m² and volume results in m³. Set the quantity for identical shapes and optionally enter a price per square or cubic metre. Convert centimetres to metres before entering dimensions: 50 cm is 0.5 m. The examples below show the formulas; the calculator does not add construction waste or convert area into volume without a height.

Area and Volume Calculator Guide

This guide calculates area and volume of boxes, rooms and tanks directly in your browser. Enter length, width and height in meters; results appear in square meters, cubic meters and liters. Interior net dimensions improve accuracy. Five to ten percent extra balances cutting losses. Everything runs locally.

Worked example and verification

These fixed inputs were checked against the tool code. Recalculate with your own amounts and rates; monetary results are rounded to two decimals.

Formula checked on: 2026-11-03

How many m² is a 400 × 300 cm rectangle?

Convert the dimensions first: 400 cm = 4 m and 300 cm = 3 m. Entering 4 and 3 gives 12 m². Entering 400 and 300 into metre fields makes the area 10,000 times too large.

400 cm = 4 m; 300 cm = 3 m; A = 4 × 3 = 12 m²

What is the volume of a 3 × 2 × 2 m box?

The volume is 12 m³. For five identical boxes, quantity 5 gives a total of 60 m³. Area (m²) and volume (m³) are different; volume needs a third dimension.

V = 3 × 2 × 2 = 12 m³; 5 × 12 = 60 m³

What is the volume of a cylinder with radius 0.5 m and height 2 m?

The result is about 1.5708 m³. Radius is half the diameter: a 1 m diameter needs radius 0.5 m. Entering diameter as radius makes the result four times too large.

V = π × 0.5² × 2 ≈ 1.5708 m³