Free Paint calculator

Estimate paint gallons and containers for rooms, walls, or ceilings. Adjust coats, opening deductions, coverage, and waste for the paint you are using.

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Paint calculator

Estimate paint gallons and containers for rooms, walls, or ceilings. Adjust coats, opening deductions, coverage, and waste for the paint you are using.

Open paint calculator
Free to use · No account required

Results update as valid measurements are entered. Check product coverage and the assumptions shown with your results.

How to calculate paint quantity

Choose Rooms for perimeter-based wall measurements, or Individual surfaces for separate rectangular areas. In room mode, select walls, ceilings, or both, then enter the shared wall height and each room’s dimensions.

Deduct door and window area under each room’s opening controls. Enter the number of coats and the product’s coverage per coat. Review container size and waste in Material settings & waste.

From surface area to containers

Room wall area is 2 × (length + width) × height. Ceiling area is length × width. The calculator uses the net paintable area, multiplies by coats, adds the waste allowance, and divides by your coverage. It then rounds up to whole containers of the size entered.

Results separate coat-adjusted coverage, paint including waste, and the amount purchased in full containers. Product coverage is an input, not a guarantee: texture, porosity, and the chosen coating can affect the amount needed.

Separate products and colors

Walls and ceilings in one calculation share the same coverage and coat count. Run separate calculations when they use different products, colors, or coat schedules. Primer, trim, and doors are excluded from this estimate. US mode uses square feet and US gallons; metric mode supports square meters and liters.

Keep the material allowance with the job

Use the quantity estimate to check supplier costs before you price the work.

Cinderblock keeps estimates, invoices, notes, and files with the job. The Build plan adds job costing from labor, materials, purchase orders, and manually entered costs. Calculator inputs do not transfer into Cinderblock automatically.

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Paint questions

The current default is two coats, but the field is editable. Check it against the coating system and surface you are planning.

Yes. Enter their combined area under Openings & exclusions for the relevant room. The deduction reduces wall area.

Yes. In Rooms mode, turn walls off and ceilings on, or use individual surfaces for rectangular ceiling sections.

No. Calculate different products and trim separately. The wall and ceiling calculation uses one product coverage and coat count.

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