How Paint Coverage Works
Paint coverage is the relationship between three variables: area to be painted, coverage rate of the paint (square feet per gallon), and number of coats. When you know any two, you can solve for the third. This bidirectional calculator handles both scenarios: "I have X square feet, how many gallons do I need?" and "I have X gallons, how much area can I cover?"
Coverage rates vary dramatically by paint type, surface texture, and application method. This calculator supports any paint via custom coverage input, with presets for the seven most common paint categories from interior latex to industrial enamels.
Bidirectional Formulas
Area to Gallons
Gallons to Area
Typical Coverage Rates by Paint Type
| Paint Type | Coverage / gal | Best For |
|---|---|---|
| Interior Latex (smooth) | 350-400 sq ft | Primed drywall, 2nd coat |
| Interior Latex (textured) | 250-300 sq ft | Knockdown, orange peel |
| Exterior Acrylic | 275-325 sq ft | Siding, trim, shutters |
| Primer (PVA) | 350-400 sq ft | New drywall |
| Stain-Blocking Primer | 250-300 sq ft | Water, smoke, bleed |
| Semi-Trans. Stain | 150-300 sq ft | Weathered deck |
| Solid Stain | 300-400 sq ft | Fences, siding |
| Oil-Based Enamel | 350-400 sq ft | Trim, doors, metal |
Why Premium Paint Has Better Coverage
Not all paints deliver their advertised coverage. Two 60-dollar gallons of "premium" paint may perform completely differently. The difference is in the solids content - the percentage of pigment and binder (by volume) in the can:
| Quality Tier | Solids | True Coverage | Price/gal |
|---|---|---|---|
| Budget | 25-30% | 200-250 sq ft | $15-25 |
| Mid-Range | 35-40% | 300-350 sq ft | $30-45 |
| Premium | 45-55% | 400-450 sq ft | $55-85 |
Color and Hide Strength
Colors with low hide strength require more coats or tinted primer:
- Best hide - white, off-white, light neutrals (1-2 coats)
- Good hide - most greens, blues, grays (2 coats)
- Poor hide - deep reds, yellows, oranges, deep blues (3+ coats or tinted primer)
For poor-hide colors, buy a tinted primer matched to your topcoat. This reduces the number of topcoats from 3+ to 2, saving time and money despite the extra primer step.
Imperial vs Metric Unit Conversion
This calculator supports both measurement systems and auto-converts between them:
European and metric-region paints are usually sold in 1L, 2.5L, 5L, and 10L tins. A typical 2.5L paint tin covers about 25-30 square meters. A 10L can covers about 100-120 square meters.