Paint Calculator
Estimate gallons of wall and ceiling paint, subtract windows and doors, and calculate multi-coat coverage.
Paint Calculator Estimator
Real-time dynamic contractor formulas
- Gross Wall Area: 630 sq ft
- Window & Door Deductions: -70 sq ft (2 doors, 2 windows)
- Net Wall Area: 560 sq ft
- Ceiling Area: 300 sq ft
How It Works: Paint Calculator
Accurate estimating requires accounting for both theoretical surface geometry and real-world manufacturer specifications. When purchasing building materials, standard packaging (such as whole cartons, pre-mixed bags, or rolls) introduces fractional waste that must be rounded up to the nearest commercial sales unit.
- Dynamic cutting and breakage waste margins based on room/project complexity.
- Automatic rounding to full retailer cartons to prevent mid-job shortfalls.
- Imperial and metric conversion parity with precision rounding.
Paint Coverage by Sheen & Surface Texture
Average square foot coverage per 1-gallon can.
| Paint Sheen | Smooth Drywall Coverage | Textured / Porous Coverage | Best Application |
|---|---|---|---|
| Flat / Matte | 380 - 400 sq ft / gal | 280 - 320 sq ft / gal | Ceilings, low-traffic adult bedrooms |
| Eggshell | 350 - 380 sq ft / gal | 275 - 300 sq ft / gal | Living rooms, dining rooms, bedrooms |
| Satin | 350 - 375 sq ft / gal | 270 - 300 sq ft / gal | Kitchens, bathrooms, hallways, kid rooms |
| Semi-Gloss | 350 - 375 sq ft / gal | 300 sq ft / gal | Doors, trim, baseboards, cabinets |
- Always apply a dedicated primer when painting over dark colors or bare drywall.
Example: 12 ft × 14 ft Bedroom with 8 ft Ceilings (2 C...
| Step | Formula / Calculation | Result |
|---|---|---|
| 1. Gross Wall Area | 2 × 8 × (12 + 14) | 416 sq ft |
| 2. Net Wall Area | 416 - 21 - 30 | 365 sq ft net |
| 3. 2-Coat Total Area | 365 × 2 | 730 sq ft total |
| 4. Gallons Calculation | 730 ÷ 350 = 2.08 → ⌈3⌉ | 3 Gallons |
Key Factors for Paint Calculator
While our formulas strictly follow IRC (International Residential Code) and ANSI standards, certain custom construction conditions require specialized engineering review:
- Extreme slopes & irregular curves: Non-rectangular perimeters require trapezoidal sub-sectioning.
- Heavy structural load-bearing applications: Commercial slabs over 3,000 PSI require soil compaction tests.
- Subfloor moisture & acclimation: Extreme humidity variations require dedicated expansion joints beyond base percentages.
FAQs: Paint Calculator
Related Tools: Paint Calculator
Planning a comprehensive renovation? Continue your estimate with these connected cluster tools:
Wall Paint Calculator
Calculate exact wall square footage and paint cans for multi-wall rooms and accent walls.
Ceiling Paint Calculator
Calculate flat ceiling paint gallons, texture absorption, and vault/cathedral angle multipliers.
Primer Calculator
Estimate stain-blocking, PVA drywall, and bonding primer gallons before topcoat application.