Vacuum calculators
Calculators and tables for vacuum technology
Convert pressure units, find the boiling point of water under vacuum and convert flows between standard and actual conditions – free and without signing up. Every page names its formulas and sources.
- 3calculators
- 16pressure and vacuum units
- IAPWS-IF97vapour pressure of water
- DIN 1343 · ISO 8778reference conditions for flows
Calculators
The calculators
Vacuum and pressure unit converter
Convert a pressure into 16 units – mbar, Pa, Torr, micron, psi and more – as absolute or gauge pressure, with the vacuum range according to ISO 3529-1.
Boiling point of water under vacuum
At what temperature does water boil at a given pressure, and which pressure belongs to a temperature? With a vapour pressure table and curve.
SCFM to ACFM and Nm³/h to m³/h
Convert standard flow (Nm³/h, scfm) and actual flow (m³/h, acfm), plus pumping speed and throughput of a vacuum pump.
Basis
How the calculators work
The conversion factors follow the definitions of the units (NIST SP 811), the vapour pressure of water follows the industrial formulation IAPWS-IF97 and, for ice, IAPWS R14-08, and the flows follow the ideal gas law with the reference conditions of the standards. Every calculation was checked against a second, independently written implementation and against the check values published in the sources. The sources are listed at the end of every page.
The calculators are no substitute for proper sizing: the choice of a vacuum pump depends on the process, the gas, the temperature and the duty. We are happy to help with that.
Which vacuum pump suits your process?
We advise on vacuum pumps from many manufacturers and supply pumps, spare parts and service.
