Estimate paint quantity for walls, ceilings, and trim
Calculating paint involves finding the total surface area of your walls and subtracting the areas that won't be painted, like doors and windows.
On average, 1 liter of paint covers about 100-120 square feet (single coat). For a standard 2-coat finish, you should plan for 1 liter per 50-60 square feet.
Yes. Subtracting doors and windows ensures you don't buy excess paint. A standard door is about 20 sq. ft. and a standard window is about 15 sq. ft.
Multiply the length of the room by the width. If your room is 10x12, the ceiling area is 120 square feet.