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Paint calculator

Estimate how many litres of paint and cans you need for your walls.

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Need Paint needed (L), 2.5 L cans? The Paint calculator derives it from Surface area (m²), Coats, Coverage (m²/L) in one step. For instance, with Surface area (m²) = 40, Coats = 2 and Coverage (m²/L) = 10 it returns Paint needed (L) = 8 and 2.5 L cans = 4.

How to use it

  1. Enter your values: Surface area (m²), Coats, Coverage (m²/L).
  2. Read the result instantly: Paint needed (L), 2.5 L cans.

Frequently asked questions

What does the Paint calculator actually compute?

It takes Surface area (m²), Coats and Coverage (m²/L) and derives Paint needed (L) and 2.5 L cans from them. The calculation is live as you type, so the result updates on every change.

What information do I need to provide?

3 values: Surface area (m²), Coats and Coverage (m²/L). Nothing else is required — no account, no file upload.

Can you show a worked example?

With Surface area (m²) = 40, Coats = 2 and Coverage (m²/L) = 10, the calculator returns Paint needed (L) = 8 and 2.5 L cans = 4. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

What happens if I enter larger values?

It moves a lot. Using Surface area (m²) = 44, Coats = 4 and Coverage (m²/L) = 20 instead, Paint needed (L) goes from 8 to 8.8 — which is why it is worth testing a few scenarios rather than trusting a single figure.

What does it give for smaller values?

Scaled down to Surface area (m²) = 36, Coats = 1 and Coverage (m²/L) = 5, Paint needed (L) comes out at 7.2. The relationship is worth checking at both ends before you rely on a single result.

When would I actually use this?

Buying the right amount at the merchant: how many tiles, how much paint, how many bags of concrete, and what it all comes to.

What is the most common mistake?

Ordering the exact calculated quantity. Cuts, breakage and pattern matching mean tiles need 10% spare and more on a diagonal layout — and a second batch rarely matches the first for colour.

How accurate is it, and what are the limits?

Estimate only — confirm quantities with your supplier.

What is the difference between the Paint calculator and the Decking boards calculator?

This one returns Paint needed (L) and 2.5 L cans; the Decking boards calculator returns Boards needed. That is the whole difference — open the one whose figure you need.

Is there a tool for the next step?

Deck stain calculator is the closest one after this: How much stain a deck needs: the surface area of the boards, the railing and the stairs, divided by the coverage of your stain — which drops for solid stains and for rough or weathered wood — times the number of coats. Enter dimensions and it returns the gallons and, optionally, the cost.

Further reading

All guides →
How-toHow Much Paint Do You Need to Paint a Room?Estimate paint by wall area, coats and the coverage on the tin — with a worked example and the 10% rule so you buy once and match the colour.How-toHow Many Tiles Do You Need? (Floor and Wall)Estimate tiles from the area to cover and one tile's size, then add for cuts and waste. Here's the method, with an example and the 10% rule.How-toHow Much Flooring Do You Need? (With Waste)Divide the room's area by a pack's coverage, then add for cuts and waste. Here's the method, with an example and how much extra to buy.How-toHow Much Wallpaper Do You Need?Measure the wall area, divide by a roll's usable coverage, then add for pattern repeat. Here's the method, with an example and why batch numbers matter.How-toHow Much Drywall Do I Need? Sheets From Room AreaTurn wall and ceiling area into a sheet count using standard panel sizes and a waste allowance, so you order the right number of drywall sheets in one go.How-toHow Many Bricks Do I Need? Calculate Bricks Per WallEstimate bricks for any wall from its area, a per-square-foot brick count, and a waste allowance — so you buy once and avoid a second trip.