Compressor Size Calculator
Choose up to three air tools that run at the same time and whether they run continuously. The calculator adds their air use at 90 psi, adds headroom and suggests the compressor, motor and tank size.
- Air needed
- Compressor size
- Tank
Pick only the tools that run at the same moment.
Size a compressor by cfm at 90 psi, plus 30% headroom. An orbital sander uses about 11 cfm, so with headroom you need about 14 cfm at 90 psi. That is a 5 hp stationary compressor with a 60 to 80 gallon tank.
Air tool cfm chart
At 90 psi. Search for a tool.
| Tool | cfm | With headroom |
|---|---|---|
| Brad nailer | 0.5 | 0.7 |
| Tyre inflation | 1 | 1.3 |
| Framing nailer | 2.5 | 3.2 |
| Air ratchet | 4.5 | 5.9 |
| Impact wrench | 5 | 6.5 |
| Die grinder | 6 | 7.8 |
| Angle grinder | 7 | 9.1 |
| HVLP spray gun | 10 | 13 |
| Orbital sander | 11 | 14.3 |
| Sandblaster | 15 | 19.5 |
cfm.
Air demand and compressor
Tools running together. Slide the air demand.
The compressor grows with the air needed.
How to size a compressor
Tools to compressor. Step through it.
Tools
List those used together.
Compare models by cfm at 90 psi, never by peak cfm.
Pancake, portable or stationary
Compressor types. Compare them.
Small.
Garage.
Workshop.
Sanders and spray guns need a stationary compressor.
Before you buy
Compressor checks. Tick each item.
Tick each item as you go.
A 240 V supply is often needed above 2 hp.
What you get
Compressor sizing. Each tile explains one result.
cfm.
hp.
Gallons.
Listed.
Continuous or not.
A compressor that is too small runs all the time and overheats.
Frequently Asked Questions
No question matches that search.
What size air compressor do I need?
Add the cfm of tools you use at once and add thirty percent.
How many cfm for an impact wrench?
About five cfm at ninety psi for a half inch wrench.
Can a small compressor run a sander?
Not well. Orbital sanders need about eleven cfm without stopping.
Does tank size matter?
A bigger tank evens out bursts but does not raise the cfm.
What does cfm at ninety psi mean?
The air flow the compressor delivers at the pressure most tools use.
How many cfm per horsepower?
About three and a half to four cfm per horsepower.
Air for every tool
Match the cfm to your tools and the compressor keeps up without straining.
More size calculators
Each one has its own calculator, worked examples and answers to common questions.