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Single conversion
To convert from hectopascal (hPa) to millibar (mbar), use the following formula:
Let's convert 5 hectopascal (hPa) to millibar (mbar).
Using the formula:
Therefore, 5 hectopascal (hPa) is equal to millibar (mbar).
Here are some quick reference conversions from hectopascal (hPa) to millibar (mbar):
| hectopascals | millibar |
|---|---|
| 0.000001 hPa | mbar |
| 0.001 hPa | mbar |
| 0.1 hPa | mbar |
| 1 hPa | mbar |
| 2 hPa | mbar |
| 3 hPa | mbar |
| 4 hPa | mbar |
| 5 hPa | mbar |
| 6 hPa | mbar |
| 7 hPa | mbar |
| 8 hPa | mbar |
| 9 hPa | mbar |
| 10 hPa | mbar |
| 20 hPa | mbar |
| 30 hPa | mbar |
| 40 hPa | mbar |
| 50 hPa | mbar |
| 100 hPa | mbar |
| 1000 hPa | mbar |
| 10000 hPa | mbar |
For all Pressure converters, choose units using the From/To dropdowns above.
A hectopascal (hPa) is a metric unit used to measure pressure.
You will most commonly see it in weather reports to describe atmospheric pressure (also known as barometric pressure).
If you've seen millibars (mbar) on older weather maps, the hectopascal is its modern replacement.
The switch was simple for meteorologists because the units are exactly the same (1 hPa = 1 mbar).
The hectopascal is now the international standard for measuring atmospheric pressure, making weather data consistent worldwide.
The conversion is in the name. The prefix "hecto-" means 100. This makes the math simple:
Just as "hecto-" means 100, "kilo-" means 1,000. This defines their relationship:
A millibar (mbar) is a metric unit used to measure atmospheric pressure.
It's most commonly used in weather forecasting and reporting.
(Technically, one millibar is equal to 0.1 kilopascal, or kPa).
Meteorologists use millibars as the primary unit to measure and report atmospheric pressure.
On weather maps, you'll see lines called isobars, which connect areas of equal pressure, drawn in millibar intervals.
Standard atmospheric pressure at sea level is about 1013 mbar.
This number is a key benchmark for weather conditions:
Yes, for all practical purposes, a millibar (mbar) and a hectopascal (hPa) are the same.
The two units are used interchangeably.
The conversion is simple: 1 mbar = 1 hPa.
While you'll still see millibars in public weather reports (especially in the U.S.), the hectopascal is the preferred SI (International System of Units) unit for global scientific consistency.
A barometer measures barometric pressure—the weight of the air above you—using millibars.
Watching the change in this reading is key to predicting the weather: