atm to mbar Converter - Standard Atmosphere to Millibar

Standard Atmosphere (atm) to Millibar (mbar)

Direct answer

1 atm = 1,013.25 mbar

mbar = atm × 1,013.25

Converter

Input

atm

Result

1,013.25mbar

mbar = atm × 1,013.25

atm = mbar × 0.000986923267

Example: 10 atm = 10 × 1,013.25 = 10,132.5 mbar.

Express both atm and mbar in the same base unit Pa (pascal), then cancel the shared base unit.

1
Rewrite atm in the base unit
$1 atm = 101, 325 Pa$
2
Rewrite mbar in the base unit
$1 mbar = 100 Pa$
3
Forward conversion
$1 atm = \frac{101 , 325 Pa}{100 Pa} \times 1 mbar = \frac{101 , 325}{100} mbar = 1, 013.25 mbar$
4
Reverse conversion
$1 mbar = \frac{100 Pa}{101 , 325 Pa} \times 1 atm = \frac{100}{101 , 325} atm = 0.000986923267 atm$

A guarded explanation for this pair page covering definition, principle, assumptions, and cautions.

Guarded output

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1 atm = 1,013.25 mbar.

10 atm = 10,132.5 mbar.

100 atm = 101,325 mbar.

Use mbar = atm × 1,013.25.

1 mbar = 0.000986923267 atm.

Use the conversion factor and round the result to the precision required by your calculation.