Air Compressor CFM Calculator
Add every pneumatic tool in your workshop or plant. The calculator totals real CFM demand with a safety factor, then suggests the compressor size and receiver tank.
Add each pneumatic tool on your assembly line, with quantity, CFM draw at 90 psi, and estimated duty cycle (% of time the tool is actually running). You'll get total continuous CFM, a recommended compressor size, and a suggested receiver-tank capacity.
Rule of thumb: receiver tank ≈ 4 gallons per continuous CFM for reciprocating units, 1–2 gallons per CFM for screw compressors with proper controls.
| Tool | Qty | CFM @ 90 psi | Duty % | |
|---|---|---|---|---|
Notes: CFM values reference 90 psi. Add 20% headroom for future expansion and derate for high ambient temperatures typical in the Gulf. For final sizing, contact our engineering team.
How the math works
1. Peak vs continuous demand — Peak demand is the sum of every tool's CFM if all ran at once. Continuous demand is that sum after multiplying each tool by its duty cycle.
2. The 25% safety factor — Add 25% on top of continuous demand to cover leaks, future expansion, and performance drop as the machine ages.
3. Receiver tank sizing — Rule of thumb: 6–10 L per CFM for piston compressors and 4–6 L per CFM for screw compressors. High intermittent loads need the upper end.
4. Working pressure — All our models are rated at 10 bar. Always compare CFM figures at the same pressure when comparing models.
Worked example
A workshop with 3 impact wrenches (5 CFM, 25% duty), 2 spray guns (12 CFM, 50% duty) and 1 sander (8 CFM, 50% duty). Continuous demand = 3.75 + 12 + 4 = 19.75 CFM. With a 25% safety factor that is roughly 25 CFM — a 7.5–10 HP compressor with a 300–500 L tank.