How much paint do I need for one room?

Calculating the amount of paint needed for a room involves measuring the walls' surface area, excluding doors and windows. This basic guide helps you estimate the quantity required without waste.

Paint calculator

Estimate
Check the can (often 8–12)
Edges, roller loading, texture
Paint needed
— L
What this includes
Total liters = (area × coats ÷ coverage) × (1 + waste%).
This is an estimate. Surface texture and absorbency can change coverage. See Disclaimer.

How the estimate works

To determine how much paint is necessary for one room, start by calculating the total wall area in square meters (m²). Measure each wall's height and width, then multiply these dimensions to get the surface area of each wall. Add up all the walls' areas except those occupied by doors and windows. Divide this figure by the coverage rate indicated on your paint can (usually given in m² per liter) to find out how many liters you need. Remember to account for touch-ups or applying multiple coats.

How to reduce the cost

FAQ

Measure each wall's height and width. Multiply these dimensions to get the surface area, then add up all walls' areas except those occupied by doors and windows.

Coverage rate indicates how much area one liter of paint can cover. It varies by brand and type but is usually found on the product label.

Primer may be necessary if you're changing colors dramatically or working with a porous surface like plaster. Check your paint's instructions for guidance.

For a general-purpose tool, see: /appliance-electricity-cost-calculator