Chemistry
STP Calculator
Convert between moles, volume and gas conditions at standard temperature and pressure.
Your inputs
Change any value to update the result instantly.
Volume at STP
22.711 L
Molar volume at STP
22.711 L/mol
Standard pressure
100 kPa
Standard temperature
273.15 K
Convention
1 bar — the current IUPAC definition, 22.711 L/mol
Which standard pressure you use matters: 22.4 L/mol belongs to the older 1 atm convention, while IUPAC's 1 bar standard gives 22.711 L/mol. Real gases deviate slightly from both.
What this calculator does
Converts between amount of gas and volume at standard temperature and pressure, with the pressure convention stated explicitly.
What your result means
The volume one mole of an ideal gas occupies under the selected standard conditions.
Formula and working
PV = nRT, with T = 273.15 K and the selected standard pressure
- 1
Collect the inputs
Standard pressure convention = 1; What do you want to find? = 1; Amount of gas = 1 mol; Gas volume = 22.711 L
- 2
Apply the formula
PV = nRT, with T = 273.15 K and the selected standard pressure
- 3
Result
Volume at STP = 22.711 L
Frequently asked questions
Symbols and assumptions
- P, V, n, T
- Pressure, volume, amount and temperature
- R
- Gas constant
- • Ideal-gas behaviour.
- • Standard temperature is 273.15 K.
Sources and review
Reviewed 2026-09-22 · Next review 2027-09-22
- • 22.4 L/mol belongs to the older 1 atm convention; IUPAC's 1 bar standard gives 22.711 L/mol. Real gases deviate slightly.
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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