Paint quantity calculator

Estimate paint quantity from area, number of coats and stated coverage.

Your inputs stay in your browser.

Method and assumptions

Method version 1.0.0 · Updated October 2, 2026

Estimate paint

Formula: Litres = converted area × coats ÷ coverage per litre × (1 + allowance).

Illustrative estimate; check product coverage and manufacturer instructions.

area: Area
areaUnit: Area unit
coats: Number of coats
coverage: Coverage per unit
coverageUnit: Coverage unit
reservePercent: Reserve allowance (%)

The estimate uses the coverage stated for the product and adds the selected reserve. Surface porosity, texture, waste and manufacturer guidance can change actual needs.

Calculate with code

These short examples use the same inputs and core calculation as this tool. Adapt validation and formatting to your application.

JavaScript

const wallArea = 42, coveragePerLiter = 10, coats = 2;
console.log(wallArea * coats / coveragePerLiter); // 8.4 L

TypeScript

const wallArea = 42, coveragePerLiter = 10, coats = 2;
const liters: number = wallArea * coats / coveragePerLiter;
console.log(liters); // 8.4

Python

area, coverage, coats = 42, 10, 2
print(area * coats / coverage)  # 8.4 L

Java

double liters = 42 * 2 / 10.0;
System.out.println(liters); // 8.4

decimal liters = 42m * 2 / 10m;
Console.WriteLine(liters); // 8.4