tinkermint.
All toolsHome
The home collection

Paint calculator.
A clearer plan.

Measure your walls, take out the openings, and get a sensible estimate of the paint you’ll need before you head to the shop.

03 / PAINT QUANTITY PLANNERMETRIC + US UNITS

Let’s size things up.

YOUR SPACE
Measurement system

Walls

Doors & windows to subtract

Enter each rectangular opening separately. Leave this section empty if you prefer not to subtract openings.

Per coat. Use your paint’s label.
For texture, touch-ups, and waste.
Rounds up whole containers of this size.

Switching units converts your current dimensions, coverage, and container size. Check the actual container size you plan to buy afterward.

Your paint plan

ESTIMATED
5 L
2 containers × 2.5 L
Wall area20.4 m²
Openings subtracted1.8 m²
Area to paint18.6 m²
Coats / coverage per coat2 / 10 m²/L
Paint before extra allowance3.72 L
With extra allowance4.092 L

A planning estimate, not a product guarantee. Porous or textured surfaces, color changes, and application method affect coverage. Primer is not included.

Results reflect the last calculation. Recalculate after editing inputs.

Calculated with TinkerMint · An estimate based on the inputs shown.

Measure once. Plan simply.

  1. For each wall, measure the width and height in the same unit. Split irregular walls into rectangles.
  2. Add the dimensions of doors or windows you don’t plan to paint. They’re subtracted from the total.
  3. Set the number of coats and the manufacturer’s stated coverage per coat. Add an allowance that fits your project.
  4. Choose your container size. The calculator rounds up to enough whole containers of that one size.

How the estimate adds up.

Net area = total wall area − openings. Paint volume = net area × coats ÷ coverage. The extra allowance is then added before rounding up to whole containers.

The default exampleTwo walls total 20.4 m². Subtract a 1.8 m² door, apply 2 coats at 10 m²/L, and add 10%: 4.092 L. With 2.5 L containers, buy 2 containers (5 L total).

US gallons are used, not UK imperial gallons. One US gallon = 3.785411784 litres; one foot = 0.3048 metres.

A few things worth checking.

Does this include ceilings, trim, or primer?

Only the surfaces you enter are included. A ceiling can be entered as a rectangle, using its length and width. Calculate trim, primer, and different paint products separately because coverage and number of coats can differ.

Why is the amount to buy higher than the estimate?

Paint is sold in containers. The planner rounds the calculated volume up to a whole number of containers of the size you choose. It doesn’t find a cheapest combination of different can sizes or compare product prices.

Should I always subtract windows and doors?

Subtract openings if you want a net-area estimate. If you choose to leave them out to allow more spare paint, remember that the extra-allowance field adds a separate margin too.