Disclosures and estimation methodology
Summary: every number on this site is an approximate estimate produced by a published formula. It is not a price quote, not a live retail price, and not professional advice. Actual quantities and costs depend on your surfaces, products, application method, contractor, and local market.
1. Nature of the estimates
Results are deterministic calculations from user inputs and fixed default parameters (Section 3). Outputs are rounded for display. Typical real-world variance for paint quantity is ±10–25%, driven mainly by surface porosity, texture, color change, and application technique. Labor and total-cost figures can vary more widely by region, season, and contractor.
2. Price data
- Paint, primer, and supplies: approximate typical US retail prices as of the review date above. They are not pulled from any retailer in real time and are not affiliated with or endorsed by any retailer or brand.
- Labor: modeled per square foot of wall area and checked against published 2026 US cost guides (Angi, HomeGuide, Homewyse). Displayed as a point estimate with a range.
- Sales tax: combined state and average local rates, midyear 2026, from the Tax Foundation. Your actual rate depends on your city, county, and district.
- All defaults can be edited by the user. Edited values replace defaults in every downstream calculation.
3. Model parameters
| Parameter | Default value |
|---|---|
| Wall area | 2 × (L + W) × H |
| Door / window deduction | 20 sq ft / 15 sq ft each |
| Paint coverage (budget / mid / premium) | 300 / 350 / 400 sq ft per gal per coat |
| Primer coverage | 300 sq ft per gal, 1 coat; spot priming = 25% of area |
| Safety margin (paint, ceiling paint, primer) | +10%, user can disable |
| Can sizing | Rounded up to quarts; 3 quarts → 1 gal; ≥ 4 gal → 5-gal bucket |
| Price factors | Quart = 0.4 × gallon; 5-gal bucket = 4.5 × gallon |
| Labor rate (lower / average / high-cost area) | $1.00 / $1.50 / $2.25 per sq ft of wall, 2 coats |
| Ceiling labor | 1.2 × wall rate |
| Coat factor (1 / 2 / 3 coats) | 0.85 / 1.00 / 1.15 |
| Primer labor factor (spot / full) | +5% / +15% |
| Wall-condition factor (good / fair / poor) | 1.00 / 1.15 / 1.35 |
| Hired-job range | −20% to +25% of the labor point estimate |
| DIY pace | ~150 sq ft per hour per coat, plus ~1.75 h prep per room |
| Recoat and dry times shown | Typical latex values; the product label always takes priority |
| Trim, doors & cabinets (optional) | Semi-gloss enamel, 400 sq ft/gal, 2 coats; baseboard 0.5 sq ft/ft, frames 0.35 sq ft/ft, door 44 sq ft (both sides), cabinet door 13 sq ft, drawer front 2.6 sq ft; cabinets get 1 coat of bonding primer |
| Trim labor (average area) | $2 per linear ft, $150 per door (both sides), $95 per cabinet door, $70 per drawer front; scaled by your labor rate ÷ $1.50. Checked against 2026 ranges of $1–$4 per ft, $40–$125 per door side, $70–$125 per cabinet door |
| Finish (sheen) suggestions | Rules only: bedrooms, living and dining rooms eggshell; primary bedroom and accent walls matte; kitchens and bathrooms satin; ceilings flat; trim, doors, cabinets semi-gloss. Kids or pets raise one level; uneven walls or a low-shine preference lower one level (not for kitchens and bathrooms) |
| Input limits (to catch typos) | Room sides up to 500 ft; up to 50 doors or windows per room; paint and primer up to $300 per gal; coverage 100–1,000 sq ft per gal; labor up to $20 per sq ft; sales tax up to 15% |
4. Quote Checker
Classifies a user-entered quote against the modeled range for the same scope. Bands: below 85% of the range floor = "unusually low"; up to the floor = "good deal"; within range = "fair"; up to 20% above the ceiling = "above average"; beyond that = "high." It does not evaluate a contractor's quality, licensing, or insurance.
5. Color preview
A client-side simulation that replaces the hue and saturation of the selected region while preserving the photo's relative luminance, so shading stays realistic. Screens, cameras, white balance, and lighting shift perceived color. The preview does not represent any manufacturer's color exactly. Always test a physical sample.
6. Questions and color suggestions
Painting questions are answered by a person, by email, as general information only, not professional advice. Color suggestions in the color tool are simple rules based on your room type, the feel you pick, and the main colors in your photo. They are ideas to test, not a match to any brand's color. Always try a real sample on your wall.
7. Regional coverage
Designed for the United States (feet, gallons, US dollars, US sales tax). Estimates are not calibrated for other countries.
8. Not professional advice
Nothing on this site is professional, legal, financial, or safety advice. For lead paint (homes built before 1978), structural issues, moisture, or mold, consult a qualified professional.
9. Trademarks and affiliations
Brand and company names mentioned on this site, such as Sherwin-Williams, Benjamin Moore, Behr, The Home Depot, Lowe's, Angi, Thumbtack, HomeAdvisor, and Buy Me a Coffee, are trademarks of their respective owners. We are not affiliated with, sponsored by, or endorsed by any of them. We do not receive payment for links on this site. If that changes, affiliate links will be clearly labeled.
10. Corrections
Found an error or an outdated price? Tell us on the feedback form or by email. We review parameters regularly and note the review date at the top of this page.