Paint Calculator
Calculate how much paint you need for any room. Enter wall dimensions, subtract doors and windows, choose paint type and number of coats to see litres needed and tins to buy.
Frequently asked questions
How much paint do I need per m²?
Standard emulsion paint covers approximately 12m² per litre. Gloss paint covers about 16m² per litre, and primer covers about 10m² per litre. These rates assume a smooth, sealed surface — bare plaster or textured surfaces use more paint.
How many coats of paint do I need?
Most walls need 2 coats for even coverage and a professional finish. You may need 3 coats when painting over a dark colour with a light one, or when using a bold colour on a white wall. A mist coat (watered-down emulsion) is recommended on new plaster.
Should I buy 2.5L or 5L tins?
5L tins are better value — typically 40–50% cheaper per litre than 2.5L tins. Buy 5L for large rooms and 2.5L for small rooms, touch-ups, or feature walls where you only need a small amount.
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InvoiceAdept lets you add paint, materials, and labour to professional invoices. Send to clients by email or WhatsApp in seconds.
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