Paint & tile
Paint Calculator
Enter room, wall or known surface measurements to find how much paint you need. Choose the number of coats, subtract openings and use the coverage listed for your paint.
YOUR MATERIAL ESTIMATE
A clearer quantity starts here.
Enter your measurements, check the units and calculate. Your result will include the assumptions and rounding steps.
Show calculation
THE WORKFLOW
How to use this paint calculator
- Choose room, individual walls or known area. Enter room dimensions, wall length/height/count or total area for that mode.
- Subtract measured openings, enter coats and product-specific coverage. Include the ceiling only in room mode if needed.
- Calculate gallons or liters; enter an optional container size to calculate whole containers.
Formula & assumptions
Room walls = 2 × (length + width) × height. Paintable area = gross walls − openings + optional ceiling. Paint = paintable area × coats / coverage.
Coverage is required from your product label and is per coat. Surface, application and product can change coverage. No universal coverage is prefilled. Room ceiling uses the same entered coverage and coat count; run separate estimates for different products or coats. Optional container counts round upward.
See methodology and sources →AN ARITHMETIC EXAMPLE, NOT A RECOMMENDATION
Worked example
Example only: 700 ft² of surface, 2 entered coats and an illustrative editable coverage of 350 ft²/US gal.
- Paintable area700 ft²
- Paintable area65.032 m²
- Total coat area1,400 ft²
- Total coat area130.064 m²
Example calculation
Paintable area: 65.032128 − openings 0 + ceiling 0 = 65.032128 m². Multiply by 2 coats; divide by entered coverage 350 ft²/US gal after area conversion = 4 US gal.
Common questions
Does paint coverage vary?
Yes. Use your product label and allow for the surface and application method. Coverage is per coat and remains editable.
Can I include a ceiling or deduct doors and windows?
Room mode has an optional ceiling control. Enter the total measured opening area in Advanced options; do not subtract openings twice.
Estimates only. Verify measurements and manufacturer packaging/yields. Project conditions vary. This tool does not provide structural engineering advice. Read the disclaimer.