Paint Quantity Calculator.
Calculate the volume of paint required for any given wall area, accounting for coats and a recommended waste buffer.
Project Parameters
Adding a 10% buffer is recommended to account for textured surfaces, spills, and roller absorption.
Volume Estimates & Waste Margins.
Why is a waste margin necessary?
No painting project uses exactly 100% of the paint inside the container. Paint gets absorbed into roller covers, gets left behind in tray linings, and goes onto tape or drop cloths. More importantly, textured or highly porous substrates (like raw plaster, brick, or stucco) absorb much more paint than smooth drywall.
We suggest a standard 10% buffer for smooth drywall, and 15% to 20% if you are painting heavily textured, unprimed, or masonry walls.
Buckets vs Cans
In the US, paint is typically sold in **1-Gallon cans** and **5-Gallon buckets**. The 5-Gallon buckets are generally cheaper per gallon (often offering a 10% to 15% cost savings), but buying a whole bucket when you only need 6 gallons means leaving 4 gallons to dry up and go to waste.
Our calculator helps you find the most logical combination, suggesting when to scale up to bulk packages to save on costs.