Convert

Hectopascal to Millibar

Exact answer: 1 hPa = 1 mbar (exact – SI decimal prefix)

Hectopascal and Millibar both belong to the Pressure family. The difference is a decimal prefix, so the factor is a clean power of ten. Pressure appears in tyre data, weather reports, hydraulics, gas cylinders and vacuum technology.

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What do you want to convert?

From1 hPa

Result1 mbar

Factor1 hPa = 1 mbar

Source basisBIPM SI Brochure · NIST Guide to SI Appendix B.8

Examples

011 hPa = 1 mbar

Example value from the reference table. Internal calculation uses stored factors; display output is rounded.

02Common mistake

bar, psi and atm appear in different fields. Tyre, weather and lab values need context.

03Base unit: Pa

1 hPa = 100 Pa. Then the value is converted through the base unit Pa into Millibar.

Table

Hectopascal to Millibar
Hectopascal	Millibar
1	1
10	10
100	100
500	500
1,000	1,000
1,013.25	1,013.25

Formula

1 hPa = 100 Pa. Then the value is converted through the base unit Pa into Millibar.

Sources

BIPM SI BrochureSI base units, prefixes and official SI context.NIST Guide to SI Appendix B.8Alphabetical conversion factors including pressure and force units.

Related conversions

Millibar to Hectopascalmbar → hPaPressure Millimetre of mercury to HectopascalmmHg → hPaPressure Inch of mercury to HectopascalinHg → hPaPressure Hectopascal to Millimetre of mercuryhPa → mmHgPressure

Search and practice paths

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Factor origin

Factors come from the stored source family and are not derived from rounded display values.

Rounding rule

UnitCloud keeps calculating with stored factors and rounds only the displayed output by selected precision.

When not to use

Do not use as the sole basis for official, medical, safety-critical or contractual decisions.

Citation

Citation note: UnitCloud, conversion with formula, sources reviewed: September 2026. Pressure. Source basis: BIPM SI Brochure · NIST Guide to SI Appendix B.8.

Common questions

What is the factor for Hectopascal to Millibar?

1 hPa = 1 mbar

Which formula does Hectopascal to Millibar use?

1 hPa = 100 Pa. Then the value is converted through the base unit Pa into Millibar.

What is the most common mistake?

bar, psi and atm appear in different fields. Tyre, weather and lab values need context.

When should I verify the result?

Do not use as the sole basis for official, medical, safety-critical or contractual decisions.