Construction
Primer Calculator
Estimate primer gallons from surface area, coats, product coverage, and allowance.
- Free to use
- Runs in your browser
- Level B · Industry formula
- Last reviewed 2026-08-16
Calculator guide
How to use the Primer Calculator
Estimate primer gallons from surface area, coats, product coverage, and allowance. Enter the requested values and select Calculate. The result and supporting values are produced locally in your browser.
Formula
Worked example
1,600 sq ft with one coat, 300 sq ft per gallon, and 5% allowance requires about 5.6 gallons of primer.
What to keep in mind
- Use the manufacturer coverage for the actual primer and substrate.
- New drywall, porous surfaces, stains, or major color changes may alter primer needs.
Methodology
This calculator uses deterministic arithmetic and performs the calculation locally in your browser. Verify assumptions, units, and source values for your specific use case.
Review standard: Level B · Industry formula. How calculator reviews work.
Frequently asked questions
What does this calculator calculate?
Estimate primer gallons from surface area, coats, product coverage, and allowance.
How is the result calculated?
Gallons = Area × Coats ÷ Coverage per Gallon × (1 + Allowance %).
Can I use the result for an important decision?
Use the result as a calculation aid and verify the inputs, assumptions, and applicable professional or regulatory requirements before relying on it for an important decision.
Does CalculateMeasure store the values I enter?
The calculator performs its arithmetic in your browser. The calculator itself does not need to send your entered values to a server to produce the result.