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LunaCalc

Conversion

ATM Conversion

Convert pressure between standard atmospheres, bar, psi, pascals, and torr.

Calculator
atm
bar
psi
Pa
Torr

About this calculator

This pressure converter translates standard atmospheres, bar, psi, pascals, and torr through a shared pascal base for science and engineering use.

Formula notes

Convert the input to pascals with the selected unit factor, then scale: atm = Pa / 101325, bar = Pa / 100000, psi = Pa x 1450377 / 1e10, and Torr = Pa x 152 / 20265.

Worked examples

  1. Example: 1 atmosphere equals 101325 Pa, 1.01325 bar, about 14.696 psi, and 760 Torr.
  2. 0.5 atm equals 50662.5 Pa, about 0.5066 bar, about 7.348 psi, and 380 Torr.

How to use it

  1. Enter a nonnegative pressure value.
  2. Choose the unit you measured.
  3. Read atmospheres, bar, psi, pascals, and torr.

Frequently asked questions

Is 1 atmosphere exactly 101325 pascals?

Yes. The standard atmosphere is defined as exactly 101325 Pa in this converter.

Are psi and Torr both supported as inputs?

Yes. Every listed unit can be selected as the input unit and converted to the rest.

Limits and interpretation

  • The converter uses exact unit definitions, so measurement uncertainty comes from the instrument, not the conversion.
  • The technical-atmosphere (at) and t/m2 units use captured reference factors and are rare in everyday pressure work.

References