Painting Cost Calculator
This Painting Cost Calculator provides two estimate modes: a quick per-square-foot calculation for rapid budgeting and a detailed room-by-room mode for contractors and homeowners who want itemized accuracy.
Estimates include paint volume, material cost, labor, and common extras such as primer, trim painting, and surface preparation. Use conservative inputs for waste and include separate primer or specialty-surface line items when applicable.
Governance
Record 9410510c0317 • Reviewed by Fidamen Standards Committee
Fast estimate using total paintable area, coats, coverage, and per-unit costs. Good for rapid budgeting.
Inputs
Results
Estimated gallons
6.2857
Paint cost
$220.00
Labor cost
$1,500.00
Total estimated project cost
$1,820.00
Cost per square foot
$1.82
| Output | Value | Unit |
|---|---|---|
| Estimated gallons | 6.2857 | gallons |
| Paint cost | $220.00 | USD |
| Labor cost | $1,500.00 | USD |
| Total estimated project cost | $1,820.00 | USD |
| Cost per square foot | $1.82 | USD |
Visualization
Methodology
Quick mode multiplies the user-supplied paintable area by coats and a user-set waste allowance, then divides by paint coverage (sqft per gallon) to estimate gallons. Costs are calculated from gallons × paint unit price plus area × labor unit price and flat preparation costs.
Detailed mode aggregates per-room wall area, deducts door and window openings, adds ceilings where provided, and separates trim, repair, primer, and specialty handling. Labor lines include area-based painting, linear-feet trim work, and repair hours multiplied by an hourly rate.
This tool follows standard measurement practices and conservative assumptions commonly used in building trades estimating. For unit and safety guidance consult national standards and regulatory resources cited below.
Worked examples
Example (quick): area_sqft=1200, coats=2, coverage=350 sqft/gal, paint_cost_per_gallon=$40, labor=$1.75/sqft → gallons ≈ (1200×1.1×2)/350 ≈ 7.54 gal, purchase 8 gal, total = paint + labor + prep.
Example (detailed): 3 rooms × 220 sqft walls, ceiling_area=300 sqft, 2 doors, 4 windows, trim 200 ft, repair_hours=4 → net area computed, trim and repair added, totals aggregated for final budget.
F.A.Q.
How do I include primer or multiple product types?
Enter primer cost as a separate line item if primer is purchased separately. For different product types (e.g., ceiling vs wall paint), run the detailed mode twice with different coverage and cost inputs and sum the totals.
How accurate are quick per-square-foot estimates?
Quick estimates are suitable for ballpark budgeting (±15–30%). Use detailed mode or a contractor quote for final budgeting, especially when repairs, multiple substrates, or hazardous materials are present.
Should I round gallons up?
Yes. Manufacturers sell whole gallons; round gallons_needed up to the next whole unit when purchasing. Also account for color changes or specialty finishes which may increase required material.
What about safety, VOCs, and lead?
Follow federal and local regulations for VOCs, lead-based paint, and worker safety. For lead hazards consult CDC guidance and use qualified abatement professionals where required. Use low-VOC products where appropriate and ensure adequate ventilation per OSHA and EPA recommendations.
Can this calculator be used for exterior projects?
Yes. Use exterior-appropriate coverage, waste allowances, and labor rates. Exterior work may require additional prep, scaffolding, and permits; include these as specialty_surface_prep or separate line items.
Sources & citations
- NIST – Weights and Measures and unit standards — https://www.nist.gov/pml
- OSHA – Worker safety guidance — https://www.osha.gov
- EPA – Indoor air and volatile organic compounds (VOCs) — https://www.epa.gov/indoor-air-quality-iaq/volatile-organic-compounds
- U.S. Department of Energy – Building and envelope guidance — https://www.energy.gov
- CDC – Lead paint safety for painters — https://www.cdc.gov/nceh/lead/prevention/painters.htm
- MIT – Building and construction research resources — https://architecture.mit.edu
- ACI — American Concrete Institute Standards — https://www.concrete.org/publications/typesofpublications/standards(codesandspecs).aspx
- ACI 211.1-91 — Standard Practice for Selecting Proportions for Concrete — https://www.concrete.org/
- ASTM International — Construction Standards — https://www.astm.org/
Further resources
Versioning & Change Control
Audit record (versions, QA runs, reviewer sign-off, and evidence).
Record ID: 9410510c0317What changed (latest)
v1.0.0 • 2025-11-20 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Public QA status
PASS — golden 25 + edge 120
Last run: 2026-01-23 • Run: golden-edge-2026-01-23
Versioning & Change Control
Audit record (versions, QA runs, reviewer sign-off, and evidence).
What changed (latest)
v1.0.0 • 2025-11-20 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Public QA status
PASS — golden 25 + edge 120
Last run: 2026-01-23 • Run: golden-edge-2026-01-23
Engine
v1.0.0
Data
Baseline (no external datasets)
Content
v1.0.0
UI
v1.0.0
Governance
Last updated: Nov 20, 2025
Reviewed by: Fidamen Standards Committee (Review board)
Credentials: Internal QA
Risk level: low
Reviewer profile (entity)
Fidamen Standards Committee
Review board
Internal QA
Entity ID: https://fidamen.com/reviewers/fidamen-standards-committee#person
Semantic versioning
- MAJOR: Calculation outputs can change for the same inputs (formula, rounding policy, assumptions).
- MINOR: New features or fields that do not change existing outputs for the same inputs.
- PATCH: Bug fixes, copy edits, or accessibility changes that do not change intended outputs except for previously incorrect cases.
Review protocol
- Verify formulas and unit definitions against primary standards or datasets.
- Run golden-case regression suite and edge-case suite.
- Record reviewer sign-off with credentials and scope.
- Document assumptions, limitations, and jurisdiction applicability.
Assumptions & limitations
- Uses exact unit definitions from the Fidamen conversion library.
- Internal calculations use double precision; display rounding follows the unit's configured decimal places.
- Not a substitute for calibrated instruments in regulated contexts.
- Jurisdiction-specific rules may require official guidance.
Change log
v1.0.0 • 2025-11-20 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Areas: engine, content, ui • Reviewer: Fidamen Standards Committee • Entry ID: e4ca9f805711
- https://architecture.mit.edu
- https://www.astm.org/
- https://www.cdc.gov/nceh/lead/prevention/painters.htm
- https://www.concrete.org/
- https://www.concrete.org/publications/typesofpublications/standards(codesandspecs).aspx
- https://www.energy.gov
- https://www.epa.gov/indoor-air-quality-iaq/volatile-organic-compounds
- https://www.nist.gov/pml
- https://www.osha.gov