What this room paint calculator calculates
A 12 × 12 ft room with 8 ft walls has 384 ft² of wall area before subtracting openings. At 400 ft² per gallon per coat, two coats need about 1.92 gallons before waste.
Formula
Paintable area × coats ÷ coverage per gallon = gallons, rounded up.
Worked example
With two coats and 10% waste, 384 × 2 × 1.10 ÷ 400 = 2.11 gallons, so 3 gallons is the practical order.
Ordering decision
Fresh drywall, porous surfaces, sheen, primer, and the product label can lower coverage.
The page cites the applicable Uzi Tools reference table beside the calculator. Product labels, current editions, local code, and a licensed professional govern structural, electrical, and life-safety work.
How to use it
- Enter the measured dimensions and keep the displayed units beside each field.
- Review the paint gallons for a room result and the substituted formula before ordering.
- Adjust waste for the layout, cut pattern, product package, and site conditions.
- Copy or print the material list, then verify the cited product data and local requirements.
Paint gallons for a room
Use this room paint calculator for wall area, openings, coats, surface, and product coverage. It targets room painting, not color advice or a generic area count.
Limits and professional review
Measurements, product yield, waste, moisture, and site conditions can change the order quantity. Local code and a licensed professional govern structural and electrical work.