Paint calculator — how much paint, sealer and putty, and what it costs
Add your rooms, kitchen, balcony or the outside of the house, tap the measurements onto the picture, pick the paint and colour, and get one shopping list. Free, no login.
Your project
How to measure
- Measure the length and width of the room along the floor, wall to wall.
- Measure the height from the floor to the ceiling.
- Count the doors and windows; their area is taken off.
- For the outside: measure the front and the side of the house, count the floors and the windows on one floor.
How a wall is painted (Berger's method)
- Clean the wall and sand it.
- One coat of sealer, thinned with water.
- Two coats of putty, then sand smooth.
- A second coat of sealer.
- Two coats of paint.
Worked examples
Two rooms 12×14 ft, 10 ft high, one door and one window each: about 960 sft of wall and 336 sft of ceiling.
A 4×5 ft window with a bar grill is about 20 sft of enamel area; two coats of enamel need about 0.4 L plus a little thinner.
Line putty or sheet putty?
Line putty is a full coat over the whole wall: the smoothest finish, about 45–55 sft per kg per coat. Sheet putty is a light pass over the uneven spots: two 12×14 rooms take about 5 kg. Ceilings are usually not puttied.
Why more paint than the tin says?
The company's coverage is measured in a lab on a smooth surface. On a real wall painters get about 60–70 % of it, so this calculator counts 65 %.
Questions
How many litres of paint for a 12×14 room?
About 480 sft of wall after a door and a window. With a washable emulsion at two coats that is roughly 10 litres — about three gallons.
Do I need sealer before paint?
Yes on new plaster: sealer stops the wall drinking the paint and keeps damp from spoiling it. On sound old paint one coat is enough.
Which putty should I use?
Acrylic wall putty inside for the smoothest finish. Cement-based All Purpose putty is cheaper and works outside too, but the wall must be wetted and it does not go on old emulsion.
Is the ceiling puttied?
Usually not. Most ceilings get sealer and a distemper or emulsion only. You can switch ceiling putty on if you want it.
Does the colour change the price?
Sometimes. Deep colours need more tinter and can cost more; pick the colour and the calculator uses its price.
Is painter labour included?
No. Labour rates differ a lot from place to place, so only the materials and small accessories are counted.
How much does it cost to paint a room?
It depends on the wall area, the paint, the number of coats and whether the wall is new or old. Enter your room above and it shows the litres of paint, sealer and putty, which cans to buy and what they cost.
What is the price of paint?
It changes with the type of paint, the can size and the shade. Pick a paint and shade in the calculator and it shows which cans to buy at Berger's list price (MRP) and the total; shops may charge a little more or less.
How many litres in 1 drum of paint?
1 drum of paint = 18 litres. That is about 4.95 gallons (18 ÷ 3.64). Work out the litres you need in the calculator and it shows how many drums, gallons and litres to buy.
How many litres in 1 gallon of paint?
1 gallon of paint = 3.64 litres (the paint-can gallon sold in Bangladesh, not the 3.785 L US gallon). 4 gallons is about 14.56 litres and 1 drum is 18 litres.