ACFM to SCFM Calculator
ACFM (Actual Cubic Feet per Minute) is the volumetric flow measured at site conditions. SCFM (Standard Cubic Feet per Minute) normalizes that flow to standard reference conditions...
Formula
Source: Engineering Toolbox, CAGI standards | Last reviewed: June 7, 2026
Examples
100 ACFM
= 100 SCFM
- T_actual = 70
- P_atm_psi = 14.7
At standard conditions, ACFM = SCFM
105.8 ACFM
= 100 SCFM
- T_actual = 100
- P_atm_psi = 14.7
Correcting hot ambient (100°F) flow back to standard
122.5 ACFM
= 100 SCFM
- T_actual = 70
- P_atm_psi = 12
Correcting high altitude flow back to standard
Where is this used?
Also used when field instruments report ACFM but system design requires SCFM values.
Frequently Asked Questions
Why convert ACFM to SCFM instead of the other way?
Manufacturers rate compressors in SCFM at standard conditions. If you measure actual flow on site (ACFM), you need this conversion to compare against the nameplate rating.
Does this use the same standard conditions as the SCFM to ACFM converter?
Yes. Both use 68°F (520°R) and 14.696 psia as standard conditions. The formulas are exact inverses of each other.
What if my site elevation is above sea level?
Enter the local barometric pressure as P_atm_psi. At 5000 ft elevation, typical barometric pressure is about 12.2 psia. The calculator adjusts for this automatically.
Reviewed for accuracy
· Last reviewed: June 7, 2026
All calculations are for reference only. Always verify with manufacturer data and a qualified engineer for critical applications. Learn about our editorial process.