ppmv to mg/m3 Gas Concentration Converter

Convert gas concentration between ppmv and mg/m3 using molecular weight, temperature, and absolute pressure.

Uses the ideal gas law for a dry gas. Water vapor, real-gas effects, ppm by mass, and liquid concentration are outside the scope of this tool.

STEP 1

Enter Gas Conditions

Select the conversion direction, then enter concentration, molecular weight, temperature, and absolute pressure.

Conversion mode

Concentration

ppmv or mg/m3, depending on the selected mode.

Molecular weight

g/mol for the target gas component.

Temperature

Temperature unit

Absolute pressure

Pressure unit

Enter gas conditions and press Convert to see the converted concentration.

mg/m3 = ppmv * molecular_weight * pressure_pa / (R * temperature_k) / 1000

ppmv = mg/m3 * 1000 * R * temperature_k / (molecular_weight * pressure_pa)

R = 8.314462618 J/(mol K). Pressure must be absolute pressure, not gauge pressure.

Enter the molecular weight of the target gas component, not the average molecular weight of the whole gas mixture.
Enter absolute pressure. If you have gauge pressure, add atmospheric pressure before using this converter.
Use the same temperature and pressure basis as the measurement, specification, or regulation you are comparing against.
For wet gas, humidity correction, real-gas effects, or legally defined reference oxygen conditions, apply the relevant method separately.