Paint for 20,633 sq ft
For 20,633 square feet you need approximately 117.90 gallons (446.3 liters) of paint (2 coats). Free paint calculator.
Coverage: 350 sq ft per gallon per coat. 20,633 sq ft x 2 coats / 350 = 117.90 gallons ≈ 446.26 liters.
How This Was Calculated
Wall Area = 2 x (Length + Width) x Height
Net Area = Wall Area + Ceiling - (Doors x 21 + Windows x 15)
Gallons = (Net Area x Coats) / 350
One gallon of paint typically covers about 350 square feet per coat (one liter covers about 8.6 square meters). Textured walls, dark-to-light color changes, and unprimed surfaces may need 10-20% more.
Quick Reference Table
| Input | Result |
|---|---|
| 20628 | 117.87 gallons (446.2 liters) |
| 20631 | 117.89 gallons (446.2 liters) |
| 20632 | 117.90 gallons (446.2 liters) |
| 20634 | 117.91 gallons (446.3 liters) |
| 20635 | 117.91 gallons (446.3 liters) |
| 20638 | 117.93 gallons (446.4 liters) |
Frequently Asked Questions
How much paint do I need for a 12x12 room?
A 12 x 12 ft room with 9 ft walls, one door, and one window needs about 2.3 gallons (8.8 liters) for two coats on the walls. Add the ceiling and you need about 3 gallons.
How much area does one gallon of paint cover?
One gallon covers approximately 350 square feet per coat on smooth, primed walls. Rough or textured surfaces may only get 250-300 sq ft per gallon.
Should I buy extra paint?
Yes — buy 10% extra for touch-ups and future repairs. Rounding up to the next full gallon is standard practice. Leftover paint keeps for years if sealed properly.
Do I always need two coats?
Two coats give the best color depth and durability. One coat may suffice when repainting a similar color over primed walls. Dramatic color changes (dark to light) may need primer plus two coats.
How do I measure an odd-shaped room?
Break the room into rectangular sections, calculate each wall separately, then add them together. For sloped ceilings, measure the wall at its average height.