💨 Engineering

Gas Flow Unit Converter

Convert volumetric gas flow between sccm, slm, L/min, m³/h, CFM and MMSCFD. Enter a value, choose the units, then press Convert.

Written and reviewed by SM Arijul Islam · Last reviewed 28 October 2026 · Editorial standards · Report an error

About the Gas Flow Unit Converter

Gas flow is only meaningful with a reference condition, because a gas expands and contracts with temperature and pressure. This converter treats every unit as a volumetric flow at standard conditions: 0 °C and 1 atm for the metric and sccm/slm units, and the conventional standard cubic foot for CFM and MMSCFD.

The core identity is simple: 1 sccm is 1 cm³/min, 1 slm is 1 L/min, and 1 m³/h is 16.667 L/min. CFM is 28.317 L/min at standard conditions. If your process is at a different temperature or pressure, convert to mass flow or correct the volume before comparing figures.

How the calculation works

1 sccm = 0.001 L/min; 1 slm = 1 L/min.
1 m³/h = 16.667 L/min; 1 m³/min = 1,000 L/min.
1 CFM = 28.3168 L/min at standard conditions.
1 MMSCFD = 19,664.5 L/min at standard conditions.

Reference values

Gas-flow equivalents
Flow unit	L/min	m³/h	CFM
1 sccm	0.001	0.00006	0.0000353
1 slm	1	0.06	0.0353
1 m³/h	16.667	1	0.5886
1 CFM	28.317	1.699	1
1 MMSCFD	19,664.5	1,179.9	694.4

Worked example: sccm, CFM and a real process

A 500 sccm mass-flow controller passes 0.5 L/min, or 0.03 m³/h, at standard conditions. A 100 CFM fan moves 2,831.7 L/min, about 169.9 m³/h. If the actual line is at 2 bar and 40 °C, the standard volumetric flow is lower than the actual flow; correct with the ideal-gas ratio before comparing the two readings.

The reference condition is the part that trips people up. This page uses 0 °C and 1 atm for the metric, sccm and slm units, and the conventional standard cubic foot for CFM and MMSCFD. Some industries use 15 °C or 20 °C instead. A flow quoted without its reference condition is incomplete, so record it alongside the number.

Frequently asked questions

What does sccm stand for?

Standard cubic centimetres per minute. The 'standard' is a defined reference temperature and pressure, not the actual gas temperature in your tube.

Can I convert CFM to sccm directly?

Yes at the same reference condition: 1 CFM = 28,316.8 sccm. If the conditions differ, correct for pressure and temperature first.

Does this handle mass flow?

No. Mass flow (g/s, kg/h) needs the gas density. This page converts volumetric flow at standard conditions.

What standard condition does this converter use?

0 °C and 1 atm (101.325 kPa) for the metric, sccm and slm units, and the conventional standard cubic foot at the same reference. Some industries use 15 °C or 20 °C; check the datasheet.

Sources and standards

A volumetric gas flow is meaningless without its reference temperature and pressure. NIST OWM defines the SI and customary units used here, and the page distinguishes actual flow from the standard-condition figures used in gas billing.