Paint Calculator: How much paint do I need?
You will have to input some raw data into the paint calculator. It includes:
- Room dimensions — You need to type in the length, width, and height of the room you plan to paint. If your room has a different shape than a rectangular cuboid, you can also input the total room wall area directly into the paint estimator. The calculated value only takes into account the walls as if there are no doors or windows.
- Doors — You can use the default dimensions of a door entered in our calculator or customize them to fit your needs. Make sure to type in the number of doors in the room so the paint calculator will find their total area. Enter
0if the room to be painted has no doors on the wall or the entry door is either on the floor or ceiling, like in an attic or basement. - Windows — Again, you can utilize the default dimensions provided or type in custom ones. Then. enter the number of windows of the same dimensions. Don’t forget to input the number of windows, whether 0 or more. If you have windows of different sizes in your room, it’s better to calculate the total area manually and input this value into the appropriate box.
- Number of coats — By default, our calculator finds the amount of paint required for one layer, but you can input the number of coats you plan to use yourself.
- Paint efficiency — This number should be written on the paint can, expressed in m²/l or ft²/l.
- Cost per unit volume — Optionally, you can input the cost of a unit of paint (cost per liter or per gallon). The paint calculator will automatically find the total cost of paint.
Is the paint estimation accurate?
Obviously, it won’t be a hundred percent accurate. If the surface is porous or rough, it will require additional paint — up to 20%. Similarly, complicated fittings require extra paint.
You also need to add some paint — up to 30% — if you are painting a surface for the very first time, as you need to prepare the wall.
Note that our interior paint calculator does not include the ceiling, so, if you want to include it, you need to plan some extra paint for that.
