Paint Calculator
Litres of paint and tins from wall area and coats
About Paint Calculator
The paint calculator works out how many liters of paint a job needs and how many tins to buy. Enter the wall area directly, or let the tool compute it from the room perimeter and height; subtract openings like doors and windows, set the number of coats, and adjust the coverage rate.
The calculation is straightforward: net area times coats divided by coverage. The defaults — 2 coats and 11 m² per liter — are typical for emulsion on smooth plaster, but coverage is the variable that matters most: porous, textured, or previously unpainted surfaces absorb more, so check your paint’s datasheet and lower the figure accordingly.
Along with the liters, you get the total area to be coated across all coats and a suggested tin combination, so you are not left mid-wall with an empty can. It is a free in-browser estimator for rooms, facades, fences — anywhere the question is “how much paint do I need.”
How to use Paint Calculator
- Choose the input mode: enter the wall area directly, or compute it from perimeter and height.
- Subtract the area of doors, windows, and other openings in m².
- Set the number of coats — two is standard for a color change.
- Adjust the coverage (m² per liter) to match your paint’s datasheet.
- Read the liters needed, the total area to coat, and the suggested tins.