Paint Calculator

Work out how many litres and tins of paint you need for a room.

m
m
m²
m²/litre

Your result

Paint needed5.1 litres
Wall area30.6 m²
2.5 litre tins3
5 litre tins2

Updates as you type. Based on 2025/26 UK figures where relevant.

How this is worked out

Multiply total wall length by height, take off doors and windows, then multiply by the number of coats. Divide by the paint's coverage (m² per litre).

Tips

  • Find your unit rates and standing charges on your latest bill or in your supplier's app.
  • Standing charges are paid every day regardless of usage.
  • Always buy materials from the same batch and add a waste allowance for cuts.

Frequently asked questions

How does the paint Calculator work?

Multiply total wall length by height, take off doors and windows, then multiply by the number of coats. Divide by the paint's coverage (m² per litre).

Where do the default energy prices come from?

They are typical UK price-cap level figures used as a starting point. Replace them with the rates on your own bill for an accurate result.

Do the DIY calculators include waste?

Most include an adjustable waste allowance. 10% is typical; complex layouts may need 15%.

Are the results exact?

They are estimates. Real usage, weather and installation details will change actual costs.

This calculator gives an estimate for general information. It isn't financial, tax, legal or medical advice. Check official figures on GOV.UK or NHS.uk, or speak to a qualified adviser.