Paint Calculator for a 3,000 sq ft Home
Estimate gallons of paint for a 3,000 sq ft space.
A 3,000 sq ft home or space has roughly 7,500 sq ft of paintable wall area at 8 ft ceilings. That's about 22 gallons for one coat or 44 gallons for two coats — the standard for a color change. Buy an extra gallon per color for touch-ups. Enter your exact room dimensions below to get a precise gallon count.
Gallons
1.81
Buy the next whole gallon
Paintable area
316 ft²
Total wall area
352 ft²
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How does the paint calculator work?
Wall area is the room perimeter × ceiling height. Subtract roughly 21 ft² per door and 15 ft² per average window, then multiply by the number of coats and divide by 350 ft²/gallon.
Formula: gallons = ((2(L+W) × H − doors×21 − windows×15) × coats) ÷ 350
What else do people ask about this calculator?
How many gallons of paint for 3,000 sq ft?
About 22 gallons for one coat or 44 gallons for two coats, based on ~350 sq ft of coverage per gallon and average 8 ft ceilings. Rough walls or dark-to-light color changes need more.
Does that include primer?
No — the gallon estimate is for finish paint only. If you're painting over new drywall, patches or a very different color, add 1 gallon of primer per 350 sq ft of wall area.
How much paint do I need for a 12×12 room?
A 12×12 room with 8 ft ceilings, 1 door and 1 window needs about 2 gallons for two coats.
How much does a gallon of paint cover?
About 350 ft² per gallon on smooth interior walls. Textured or porous surfaces reduce coverage to 250–300 ft².
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Where can I learn more about these materials?
Weights, coverage, types and buying tips for the materials this calculator estimates.
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