Free tool · paint
How much paint?
I measure the room and take the doors off the area before I decide how many tins to pick up.
This page turns a room, or a wall area you already have, into litres of paint and a mix of 2.5, 5 and 10 litre tins. The coverage starts at the Dulux Trade Vinyl Matt figure, and you can change it. The figures stay in the browser.
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How the litres are worked out
Walls are twice the length plus the width, times the height. The ceiling is the length times the width, unless you leave it out. Doors and windows come off the walls. You type the opening. This page does not assume a door size. Litres are the area to paint, times the coats, divided by the square metres per litre. The result is rounded up to the millilitre.
The starting coverage is up to 17 m² per litre, from the Dulux Trade Vinyl Matt data sheet (opens in a new tab). That is a guide under normal conditions, not a bare-wall promise. Lower the box if the wall is thirsty, or type the figure from the tin you are buying. Dulux Decorator Centre (opens in a new tab) says the normal finishing process is 2 full coats, and that 1 coat may be enough on a sound surface in a similar colour. The 2.5 L, 5 L and 10 L tins are pack sizes in the Dulux Trade professional product guide (opens in a new tab). Read on 18 October 2026.
The tin mix is the combination with the least paint left over, then the fewest tins. It does not know what the merchant has on the shelf. A shaped room, a stair, or a lot of cutting-in will not match a plain box. Other free tools are on the tools page.
Common questions
Why is the coverage 17 square metres per litre?
That is the top of the Dulux Trade Vinyl Matt guide: up to 17 square metres per litre under normal conditions, read on 18 October 2026. It is a starting figure, and the box can be changed. A bare or thirsty wall will not do 17. Use the figure on the tin you are actually buying.
Why does it start at 2 coats?
Dulux Decorator Centre says the normal finishing process for that paint is 2 full coats, and that 1 coat may be enough on a previously painted surface in good condition where similar colours are used. Change the coats box to match the job.
How are the tins chosen?
From 10 litre, 5 litre and 2.5 litre tins, which are pack sizes in the Dulux Trade professional product guide. The mix is the one with the least paint left over, then the fewest tins. It does not know what your merchant has in stock.
Does this take the ceiling and the doors off properly?
Walls are twice the length plus the width, times the height. The ceiling is length times width, if you leave it included. Door and window openings are subtracted from the walls, not from the ceiling. You type the opening size. This page does not assume a door size.