Inputs All fields support decimals
Example projects
| Use | Scenario | Area | Coats | Coverage | Eff.% | Prod. | Machine | Tip |
|---|---|---|---|---|---|---|---|---|
| Bedroom repaint | 900 | 2 | 375 | 65 | 450 | 0.50 | 415 | |
| Exterior siding | 2200 | 2 | 325 | 55 | 600 | 0.60 | 519 | |
| Block wall primer | 1500 | 1 | 200 | 50 | 400 | 0.79 | 623 |
Click Use to auto-fill the form with that row's inputs.
Results
Theoretical paint
—
Adjusted total
—
Estimated spray time
—
Required flow for schedule
—
Tip flow @ 2000 psi
—
Machine max flow
—
Fan width (approx)
—
Tips: Required flow is derived from coverage and production goals.
Actual spraying limited by the lesser of tip flow and machine capacity.
Actual spraying limited by the lesser of tip flow and machine capacity.
Formula used
- Theoretical volume (gal) =
Area(ft²) × Coats ÷ Coverage(ft²/gal) - Adjusted total (gal) =
Theoretical ÷ (TransferEfficiency/100) × (1 + SafetyMargin/100) - Required flow (gpm) =
[ProductionRate(ft²/hr) ÷ Coverage(ft²/gal)] ÷ 60 - Tip flow (gpm) ≈ from orifice at ~2000 psi (reference table)
- Fan width (in) ≈
FirstDigit × 2at ~12 in standoff - Estimated spray time (hr) =
AdjustedTotal(gal) ÷ min(TipFlow, MachineMax) ÷ 60
Metric inputs are converted internally (1 gal = 3.785 L; 1 m² = 10.7639 ft²).
How to use this calculator
- Select your unit system.
- Enter total paintable area and number of coats.
- Provide product coverage rate at the desired film build.
- Set transfer efficiency and any safety/waste margin.
- Choose a target production rate, your machine capacity, and a tip.
- Press Calculate to see volumes, flows, time, and checks.
- Export results as CSV or PDF, or copy a shareable link.
FAQs
Airless setups often achieve 50–70% depending on pressure, tip, angle, and skill. If unsure, start at 60% and adjust with experience or field tests.
The last two digits are orifice in thousandths of an inch, which strongly affects flow. The first digit ×2 approximates fan width in inches at about 12 inches away.
Yes, but gains are limited and may raise overspray. This tool uses approximate flow at ~2000 psi. Follow coating and equipment recommendations for pressure settings.
Time is based on fluid delivery limits and adjusted volume. Real productivity also depends on masking, staging, detail work, refills, filter clogs, and site logistics.
Yes—set lower coverage rates, expect larger tips (e.g., 0.021–0.025 orifice), and ensure your machine’s maximum flow exceeds the chosen tip’s demand.
If your spec requires back-rolling, include it as an additional coat and adjust coverage to match the roller’s spread rate for that coat.
Worn tips flow more and create more overspray. Increase safety margin and verify finish quality. Replace tips regularly per manufacturer guidance.
Example tip flow reference (approximate @ 2000 psi)
| Orifice (in) | Common codes | Approx. flow (gpm) | Typical uses |
|---|---|---|---|
| 0.011 | 311, 411 | 0.15 | Stains, thin enamels |
| 0.013 | 413, 415 | 0.24 | Interior latex walls |
| 0.015 | 415, 515 | 0.31 | Walls, primers |
| 0.017 | 517 | 0.39 | Exteriors, heavy latex |
| 0.019 | 519, 619 | 0.47 | Exterior build coats |
| 0.021 | 521, 621 | 0.57 | Block fill, primers |
| 0.023 | 523, 623 | 0.67 | Elastomerics |
| 0.025 | 525, 625 | 0.79 | Heavy bodied coatings |
Values are typical approximations; always consult current manufacturer data and safety data sheets.
Coating Type • Tip Range • Coverage Guide
| Coating | Common tip codes | Orifice (thou) | Typical coverage (ft²/gal) | Notes |
|---|---|---|---|---|
| Stain / lacquer / thin enamel | 311–413 | 0.011–0.013 | 400–600 | Low viscosity, fine finishes, narrow fans indoors. |
| Interior wall latex (eggshell) | 413–415 | 0.013–0.015 | 325–400 | Common interiors; balance fan width with room size. |
| PVA primer / drywall sealer | 515–517 | 0.015–0.017 | 250–350 | Porous substrates require lower coverage assumptions. |
| Exterior acrylic latex | 517–521 | 0.017–0.021 | 250–350 | Wider fans; watch wind and overspray outdoors. |
| Block filler / heavy primers | 621–625 | 0.021–0.025 | 75–150 | High build; verify pump capacity and filter mesh. |
| Elastomeric wall coatings | 623–625 | 0.023–0.025 | 50–100 | Very heavy; short hoses and large pumps preferred. |
Guidance is approximate. Always confirm with current product data sheets and your pump rating.
Pump Class & Capacity Quick Reference
| Pump class | Max flow (gpm) | Practical max tip | Typical applications |
|---|---|---|---|
| Handheld / small electric | ~0.27 | Up to 0.015 | Trim, doors, stains, touch-ups, small rooms. |
| Contractor mid-size | ~0.47–0.63 | Up to 0.021 | Interior walls, ceilings, most exterior latex work. |
| High-output pro rig | ~0.79–1.20 | 0.023–0.031 | Elastomerics, block fill, long hoses, large exteriors. |
Values are generalized. Check your exact model’s maximum tip size and delivery rate.
Production Rate Benchmarks (spray application only)
| Scenario | Typical team setup | Production (ft²/hr) | Notes |
|---|---|---|---|
| Empty interiors, walls & ceilings | 1 sprayer + 1 helper | 500–800 | Minimal obstacles; broad fans; fast staging. |
| Occupied interiors, frequent cut-ins | 1 sprayer | 250–450 | Furniture, masking, and protection slow progress. |
| Exterior lap siding, walkable | 1–2 sprayers | 400–700 | Wind affects overspray; plan passes and shielding. |
| Concrete block primer | 1 sprayer + back-roller | 300–500 | Porosity adds material; may require additional coat. |
| Fences (plank/board) | 1 sprayer | 300–600 | Many edges; distance and angle impact efficiency. |
| Deck railings / balusters | 1 sprayer | 150–300 | Detail work; narrow fans and lower flow helpful. |
Rates exclude masking, surface repairs, setup, cleanup, and travel time.