Find the boiling point of water at any pressure with the Antoine equation, in Celsius and Fahrenheit.
No advanced options for this tool.
Boiling point
How to use this tool
Enter pressure.
Choose kPa, atm, mmHg, bar or psi.
Read the boiling point in Celsius and Fahrenheit.
Check whether the result is inside the fitted range.
Formula & worked example
Water at 101.325 kPa (1 atm, 760 mmHg) boils at 100.00 °C (212.00 °F); at 50 kPa it boils at about 81.3 °C.
Limitations — read this before you rely on it
Pure water and the fitted Antoine range only: extrapolation beyond about 1–100 °C and impure water reduce accuracy.
Frequently asked questions
An empirical vapour-pressure curve: log10 P = A – B/(C + T), with constants fitted for each liquid over a stated range.
Different constant sets fit different ranges; this tool uses the common water set fitted for about 1–100 °C.
Higher pressure raises the boiling point, as in a pressure cooker, but this constant set extrapolates beyond its fit there.
Yes, dissolved substances raise the boiling point separately; see the boiling-point elevation tool for that.
Choose the unit in the tool; 1 atm = 101.325 kPa = 760 mmHg = 1.01325 bar = 14.696 psi.