MyYardCalc
Construction · Material planning

Paint Calculator

Estimate interior wall paint and whole cans from room dimensions, coat count and labeled coverage. Include the ceiling or subtract openings.

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US & metric

Example values are filled in. Replace them with your measurements.

ft
ft
ft
sq ft
sq ft / US gal
US gal
%

An editable purchasing margin, not a measured compaction rate.

$

Enter your measurements

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The calculation

Paint = net surface × coats × allowance factor ÷ labeled coverage per coat. Cans round up.

  • US mode uses US gallons. Coverage is product-specific and is entered per coat.

Saved on this device

Only estimates you choose to save are stored here.

    Measure with a little context

    How to use this paint calculator

    Use the product’s coverage per coat. Rough or porous surfaces and major color changes can alter actual consumption.

    Primer and finish coats are separate products. Run the calculator for each coating using its own coverage and can size.

    Paint = net surface × coats × allowance factor ÷ labeled coverage per coat. Cans round up.

    A worked example

    With the example values shown below, the calculated result is 2.081 US gal. These are demonstration inputs, not installation specifications.

    View the example measurements
    • Room length: 12 ft
    • Room width: 10 ft
    • Wall height: 8 ft
    • Openings to subtract: 21 sq ft
    • Number of coats: 2
    • Product coverage per coat: 350 sq ft / US gal
    • Paint can size: 1 US gal
    • Extra allowance: 10 %

    From estimate to order

    Whole packages and pieces round up; measured lengths, areas and volumes keep full precision during calculation. Match the product dimensions and units to your quote, and check cuts, minimum orders and delivery before purchasing.

    Read our formulas, rounding rules and limitations →

    Calculate primer and finish as separate products

    Use the net surface area for each product, its own number of coats and its labeled coverage per coat. A 300 sq ft surface with two finish coats at an illustrative 350 sq ft per gallon needs 600 ÷ 350 = 1.714 gallons. With 1-gallon cans, that is 2 cans. A separate primer coat at 200 sq ft per gallon needs 1.5 gallons, also 2 one-gallon cans.

    The resulting four cans are a purchase quantity for two different products, not four coats. Calculate ceilings or trim separately if they use another product or coverage rate. This tool does not estimate painting labor or choose the appropriate coating system.

    Paint planning questions

    How does the paint coverage calculator handle two coats?

    It multiplies the net surface area by the number of coats, then divides by the product’s coverage per coat. Enter the coverage from the actual paint label. The same wall area should not be entered twice merely because you selected two coats.

    Do I include primer in the same paint estimate?

    Calculate primer and finish paint separately with each product’s own coverage and package size. Surface porosity and application method can change consumption. This model uses rectangular-room surfaces and is not an exterior-elevation or fence-stain estimator.

    How do I calculate paint for one room?

    For rectangular-room walls, use 2 × (length + width) × height, then subtract openings. Add the ceiling only if it will use the same paint system. Multiply by coats, divide by labeled coverage per coat and round to whole cans. Calculate different products, including primer, separately.

    Calculation notes updated . Formulas, sources and limitations.

    Keep your project moving.

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