Paint Calculator
Calculate the exact amount of paint needed for walls and ceilings. Accounts for windows, doors, and second coat requirements.
Paint Calculator
Calculate the exact amount of paint needed for walls and ceilings, accounting for windows, doors, and multiple coats.
What to calculate next
Once paint volume is clear, the next practical move is usually palette planning or a room-level finish budget.
Why professionals choose this paint calculator
- Accurate calculation with all factors. Accounts for windows, doors, number of coats, and paint coverage per m².
- Windows and doors accounted for. Automatically subtracts opening areas for accurate calculation.
- Flexible settings. Adjust the number of coats and paint coverage depending on surface type.
- Mobile version. Works on all devices — calculate paint consumption anywhere.
- Free and no registration. Use the calculator without restrictions.
Step-by-step paint calculation guide
- Enter room dimensions: length, width, and wall height in meters.
- Specify the number of windows and doors — the calculator will automatically subtract their area.
- Choose the number of paint coats (usually 2 coats for quality coverage).
- Enter paint coverage per m² (usually 8-12 L/m², indicated on the can).
- Get accurate calculation in liters and add 10% extra for safety.
💡 Tip: Always buy paint with a small reserve (10-15%) for unexpected situations and touch-ups.
Common calculation mistakes
Using floor area instead of wall area. Paint is bought for walls and ceilings, not for the room footprint. That shortcut usually leaves you short on material.
Ignoring surface absorption. Fresh filler, dark previous paint and textured walls all use more paint than a smooth primed surface.
Planning for a single coat. One coat is rarely enough for an even finish in a real room. In most cases you should budget for at least two.
What to check before buying
Match the coverage to the actual product. Different paints cover differently. The safest input is the coverage printed on the exact can you plan to buy.
Buy the full amount from one batch. Slight batch variation is still visible on long walls and in rooms with strong side light.
Keep a touch-up reserve. A 10–15% reserve is cheap insurance for corners, repairs and the small fixes that show up after move-in.
Paint calculation FAQs
How to correctly calculate paint consumption?
Enter accurate room dimensions, specify the number of windows and doors, choose the number of coats and paint coverage. The calculator will automatically account for all factors and give you an accurate result.
How many coats of paint should be applied?
Usually 2 coats are enough for quality coverage. For dark colors or when painting over dark paint, 3 coats may be needed.
Should I account for extra paint when buying?
Yes, always add 10-15% to the calculated amount for unexpected situations, touch-ups, and possible application errors.
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