Use the Paint Quantity Calculator to estimate paint quantity from area, coat count, product coverage and a waste/touch-up allowance. The tool shows its assumptions so you can change them rather than relying on a hidden market average.
Paint quantity—Use the coverage printed on your paint product for best results.
Formula used
quantity = paintable area × coats ÷ product coverage × (1 + waste allowance)
How to use the result
- Enter measurements or rates you can verify.
- Check the result for obvious unit mistakes.
- Save the assumptions with your project notes.
- Replace estimates with product data or real quotations as they become available.
Important limitations
- Coverage varies by product and substrate
- Doors, trim and ceilings may need separate measurements
- Colour changes and porous surfaces can require extra coats
Before you buy or sign
- Verify measurements on site
- Use product-specific coverage or waste guidance where available
- Confirm taxes, delivery, permits, labour and disposal separately when relevant
- For safety-critical or structural work, use an appropriately qualified professional
Why RepairCostPilot shows the assumptions
A calculator is useful only when you can see what drives the result. These tools deliberately use simple inputs and avoid pretending that one national figure is an exact local contractor price.