Paint Coverage Calculator

This calculator helps you work out exactly how much paint to buy for your next painting project. It supports two input modes:

• Room Dimensions — enter your room length, width, and ceiling height. The calculator automatically computes the wall and ceiling area, subtracting standard door and window openings.
• Manual Area — enter the total area directly if you have already measured it or are painting a non-standard surface like a fence or feature wall.

Select your paint type to use typical Australian coverage rates (based on manufacturer data from brands like Dulux and Taubmans), or enter a custom coverage rate from your paint tin. Choose the number of coats (two is standard), and the calculator gives you the total litres needed plus a recommended combination of 10 L, 4 L, and 1 L tins optimised to minimise waste.

The formula used is litres = (area x coats) / coverage rate. All calculations run entirely in your browser with no data sent to any server.

Australian paint manufacturers such as Dulux, Taubmans, and Wattyl publish coverage rates on every tin. These rates represent the area one litre of paint will cover on a smooth, sealed surface in a single coat. Actual coverage depends on surface porosity, texture, colour, and application method (brush, roller, or spray).

Interior Paint Types

• Flat / Matt (12 m²/L) — hides imperfections well, ideal for ceilings and low-traffic walls. Not as washable.
• Low Sheen (14 m²/L) — the most popular choice for living areas and bedrooms in Australia. Good balance of appearance and washability.
• Semi-Gloss (16 m²/L) — more durable and washable, commonly used for kitchens, bathrooms, and trims.
• Gloss (16 m²/L) — highly durable and easy to clean, used for doors, trims, and high-moisture areas.

Preparation Tips

• Always apply a primer or undercoat on new plaster, bare timber, or when making a dramatic colour change.
• Sand glossy surfaces lightly before repainting to ensure the new coat adheres properly.
• Fill cracks and holes with a quality filler, sand smooth, and spot-prime before applying topcoats.
• Use painter's tape to protect edges, skirting boards, and window frames for a clean finish.
• Buy 5–10% extra paint to account for touch-ups, wastage, and surface absorption.