Millibars to Atmospheres Converter

Enter the pressure in millibars below to get the value converted to atmospheres.

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1 mbar = 0.000987 atm

Do you want to convert atmospheres to millibars?

How to Convert Millibars to Atmospheres

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To convert a measurement in millibars to a measurement in atmospheres, multiply the pressure by the following conversion ratio: 0.000987 atmospheres/millibar.

Since one millibar is equal to 0.000987 atmospheres, you can use this simple formula to convert:

atmospheres = millibars × 0.000987

The pressure in atmospheres is equal to the pressure in millibars multiplied by 0.000987.

For example, here's how to convert 5,000 millibars to atmospheres using the formula above.
atmospheres = (5,000 mbar × 0.000987) = 4.934616 atm

Millibars and atmospheres are both units used to measure pressure. Keep reading to learn more about each unit of measure.

What is a Millibar?

One millibar is equal to one-thousandth of a bar, which is defined as the pressure of one newton per square meter. One millibar is also equal to one hectopascal.

The millibar is a non-SI metric unit for pressure. In the metric system, "milli" is the prefix for thousandths, or 10-3. Millibars can be abbreviated as mbar; for example, 1 millibar can be written as 1 mbar.

Learn more about millibars.

What is an Atmosphere?

The atmosphere is a reference measure of pressure equal to 101,325 pascals or 1,013,250 dynes. The atmosphere was originally defined as the pressure of 760 millimeters of mercury at standard gravity at 0 °C, but was later redefined in 1954 to be equal to 1,013,250 dynes.

Atmospheres can be abbreviated as atm; for example, 1 atmosphere can be written as 1 atm.

Learn more about atmospheres.

Millibar to Atmosphere Conversion Table

Table showing various millibar measurements converted to atmospheres.
Millibars Atmospheres
1 mbar 0.000987 atm
2 mbar 0.001974 atm
3 mbar 0.002961 atm
4 mbar 0.003948 atm
5 mbar 0.004935 atm
6 mbar 0.005922 atm
7 mbar 0.006908 atm
8 mbar 0.007895 atm
9 mbar 0.008882 atm
10 mbar 0.009869 atm
20 mbar 0.019738 atm
30 mbar 0.029608 atm
40 mbar 0.039477 atm
50 mbar 0.049346 atm
60 mbar 0.059215 atm
70 mbar 0.069085 atm
80 mbar 0.078954 atm
90 mbar 0.088823 atm
100 mbar 0.098692 atm
200 mbar 0.197385 atm
300 mbar 0.296077 atm
400 mbar 0.394769 atm
500 mbar 0.493462 atm
600 mbar 0.592154 atm
700 mbar 0.690846 atm
800 mbar 0.789539 atm
900 mbar 0.888231 atm
1,000 mbar 0.986923 atm
2,000 mbar 1.9738 atm
3,000 mbar 2.9608 atm
4,000 mbar 3.9477 atm
5,000 mbar 4.9346 atm
6,000 mbar 5.9215 atm
7,000 mbar 6.9085 atm
8,000 mbar 7.8954 atm
9,000 mbar 8.8823 atm
10,000 mbar 9.8692 atm

More Millibar & Atmosphere Conversions