🎨 Bathroom Paint Calculator
Enter your bathroom's dimensions, the number of coats, and how many doors and windows it has to see the paintable area and exactly how many gallons to buy — no half-empty cans, no mid-job runs to the store.
🧮 Estimate Your Paint
🎨 Paint you'll need
| Wall area | 224 sq ft |
| Ceiling area | 0 sq ft |
| Paintable area (after doors & windows) | 188 sq ft |
| Total across coats | 376 sq ft |
| Gallons to buy | 2 |
Buy the right amount, once
Buy too little paint and you're back at the store mid-coat, hoping the new can matches; buy too much and you've paid for gallons that gather dust in the garage. The trick is knowing your true paintable area — the walls and, if you like, the ceiling, minus the doors and windows you skip.
This calculator does that math and factors in your number of coats before turning it into gallons at the standard 350-square-foot coverage. In a steamy room, pair the estimate with a moisture-resistant semi-gloss or satin finish that shrugs off condensation and wipes clean.
❓ Frequently Asked Questions
How much wall area does a gallon of paint cover?
A gallon typically covers about 350 square feet in one coat on a smooth, primed surface — the figure this calculator uses. Rough, porous, or unprimed walls drink more, and a dramatic color change often needs a second coat, so the tool multiplies your paintable area by the number of coats before converting to gallons.
How are doors and windows handled?
The calculator subtracts a standard 21 square feet for each door and 15 square feet for each window from the wall area, since you don't paint those. If your openings are unusually large or small, adjust the counts to approximate the real surface — the deductions never push the paintable area below zero.
What kind of paint is best for a bathroom?
Bathrooms are humid, so choose a moisture-resistant paint in a semi-gloss or satin finish. Those sheens resist steam, wipe clean, and discourage mildew far better than a flat finish. Many brands sell a dedicated bathroom or kitchen-and-bath paint with mildew-resistant additives — worth it in a room that gets a hot shower every day.
Should I include the ceiling?
If you're repainting the ceiling too, tick the box and the tool adds the room's floor-plan area (length × width) to the total. Bathroom ceilings take a lot of steam, so a mildew-resistant ceiling paint is a smart choice. Leave it unchecked to estimate walls only.