๐จ How Much Paint Do I Need?
Running out of paint mid-wall means a rushed second trip โ and possibly a color mismatch. Overbuying wastes $50โ$100. Here's the exact formula for any room.
1 gallon covers ~350โ400 sq ft per coat. A standard 12'ร12' bedroom (walls only) needs ~1.5 gallons for 2 coats. Calculate your exact gallons with the Paint Calculator.
๐ The Formula (Simple)
Wall Area = 2 ร (Length + Width) ร Height
Then:
- Subtract 20 sq ft per door
- Subtract 15 sq ft per window
- Multiply by number of coats (usually 2)
- Divide by 375 (avg coverage per gallon)
- Round up to nearest gallon
๐ Room-by-Room Paint Needs
| Room | Walls (2 coats) | + Ceiling | + Trim |
|---|---|---|---|
| Small bedroom 10ร10 | 1 gal | +0.5 gal | +1 qt |
| Standard bedroom 12ร12 | 1.5 gal | +0.5 gal | +1 qt |
| Living room 15ร20 | 2.5 gal | +1 gal | +1 qt |
| Kitchen 10ร12 | 1.5 gal | +0.5 gal | +1 qt |
| Open floor plan 20ร30 | 5 gal | +2 gal | +2 qt |
Get exact gallons with the Paint Calculator โ it handles any room size, doors, windows, and trim.
๐จ Paint Finish Guide
Bedrooms, ceilings ยท Best for low-traffic areas ยท Hard to clean
Living rooms, hallways ยท Washable ยท The all-purpose choice
Kitchens, kids' rooms ยท Easy to clean ยท Slight sheen
Bathrooms, trim, doors ยท Most durable ยท Very shiny
๐ก Pro Tips to Save Money
- Buy 10% extra โ Keep for touch-ups (write room + date on lid)
- Use primer โ Needed for dark-to-light or raw drywall
- Match color codes โ Save the label with the mix code
- Buy quality brushes/rollers โ Cheaper in labor saved
- Paint the ceiling 1 shade lighter โ Visually raises ceilings
- Save receipts โ Many stores accept returns on unopened gallons
Going from dark to light? Painting new drywall? Changing finish (matte โ gloss)? You need primer. Without it, you'll need 3โ4 coats and spend more on paint than primer would've cost.
โ FAQ
How much does a gallon of paint cover?
Roughly 350โ400 sq ft per coat on smooth surfaces. Textured walls or rough surfaces cover less โ around 250โ300 sq ft.
How many coats of paint do I need?
Two coats for most projects. One coat works if you're refreshing the same color. Three-plus if you're changing drastically (dark to light, matte to gloss, or over raw drywall).
Do I need to paint the ceiling and trim?
Not always. If they're in good shape, leave them. If they're scuffed or a different color, add ~1 gallon for ceiling and ~1 quart for trim per room.
Can I use the same paint on walls and trim?
Yes, but trim takes more abuse โ use semi-gloss or satin for durability. Wall paint is generally too flat for trim.
Calculate Your Paint Needs
Free calculator โ enter room size, coats, and trim for exact gallons + cost.
๐งฎ Try the Paint Calculator โ