Paint Coverage Calculator
Find out exactly how much paint your rooms need — add wall sizes, doors, windows and coats, and get the liters needed plus the smartest tin sizes to buy.
For each room enter the total wall length to paint (sq ft) and the wall height (ft).
How to use
- Choose Measure Rooms or Total Wall Area.
- If measuring rooms, add one row per room: total wall length (sq ft) x wall height (ft). You can add up to 6 rooms.
- Enter how many doors and windows will not be painted — their area is subtracted automatically.
- Pick the number of coats (1–3) and the paint coverage from the tin label (default 120 sq ft per liter).
- The paintable area, liters needed and the best 1L / 4L / 20L tin combo update instantly.
Tips
- Buy the recommended tin combo — it is chosen to leave the least leftover paint.
- Always get 10% extra paint for touch-ups; one small tin extra is usually enough.
- Rough or textured walls drink more paint — lower the coverage value to 90–100 sq ft per liter.
- Two thin coats last longer and look better than one thick coat.
- Keep leftover paint sealed and labelled — it is perfect for future touch-ups.
Frequently Asked Questions (FAQ)
How do I enter my room sizes?
Choose Measure Rooms and add one row per room, up to 6 rooms, with the total wall length in sq ft and the wall height in ft. Or choose Total Wall Area and enter the number directly.
How are doors and windows handled?
Enter how many doors and windows will not be painted. Each door subtracts 21 sq ft and each window subtracts 15 sq ft automatically.
What tin sizes does the calculator recommend?
The Buy This Combo result mixes 1L, 4L and 20L tins to cover the liters you need with the least leftover paint.
What paint coverage value should I use?
Use the coverage printed on your tin label. The default is 120 sq ft per liter; most wall paints cover 100 to 140 sq ft per liter. For rough or textured walls, lower it to 90 to 100.