Wall Paint Calculator

Planning to refresh your space with a new coat of paint? Our Wall Paint Calculator makes it easy to figure out exactly how much paint you’ll need for your next project. Whether you’re tackling one room or your entire home, this tool takes the guesswork out of the process, helping you save time, money, and unnecessary trips to the hardware store.

Tips Before You Start

1. Measure Twice, Paint Once
Be as accurate as possible when measuring your walls. Include windows and doors in your inputs—they make a difference when calculating paint needs.

2. Don’t Forget the Second Coat
Most paint jobs require two coats for full coverage, especially if you're switching to a lighter color. Make sure to double your total if you're planning on going over your walls twice.

3. Factor in Surface Type
Porous surfaces like drywall or raw plaster can absorb more paint, while glossy or previously painted walls may need less. Use a primer first if you're painting over a dark color or a tricky surface.

4. Consider Extra for Touch-ups
It’s always smart to buy a little more paint than you need. Walls get scuffed, colors fade, and touch-ups are easier when you have the exact match on hand.

Frequently Asked Questions

How accurate is this calculator?
Our calculator gives you a reliable estimate based on your inputs. For best results, make sure your measurements are accurate and round up slightly to account for errors or extra coats.

How much paint is typically needed per square foot?
A gallon of paint usually covers about 350–400 square feet with one coat. Keep in mind that textured or absorbent walls may need more.

Should I include windows and doors in my wall measurements?
Yes! Our calculator allows you to subtract those from the total area, so you get a more precise estimate.

What about ceilings or trim?
This tool is focused on wall surfaces only. If you're painting ceilings or trim, you'll need to measure those separately and calculate additional paint.