Atmospheres to Millipascals Converter
Enter the pressure in atmospheres below to convert it to millipascals.
Convert Atmospheres to Millipascals
Enter a value in atmospheres (atm) to convert to millipascals (mPa).
Standard Atmosphere to Millipascal Conversion Table
Table showing various standard atmosphere measurements converted to millipascals. Click any preset value or arrow to load it into the converter.
| Atmospheres (atm) | Millipascals (mPa) |
|---|---|
| 0.0000001 atm | 10.1325 mPa |
| 0.0000002 atm | 20.265 mPa |
| 0.0000003 atm | 30.3975 mPa |
| 0.0000004 atm | 40.53 mPa |
| 0.0000005 atm | 50.6625 mPa |
| 0.0000006 atm | 60.795 mPa |
| 0.0000007 atm | 70.9275 mPa |
| 0.0000008 atm | 81.06 mPa |
| 0.0000009 atm | 91.1925 mPa |
| 0.00000001 atm | 1.01325 mPa |
How to Convert Atmospheres to Millipascals
To convert atmospheres to millipascals, multiply the pressure by the following conversion ratio: 101,325,000 millipascals/standard atmosphere.
Since one standard atmosphere is equal to 101,325,000 millipascals, you can use this simple formula to convert:
The pressure in millipascals is equal to the pressure in atmospheres multiplied by 101,325,000.
For example, here's how to convert 5 atmospheres to millipascals using the formula above.
How Many Millipascals Are in a Standard Atmosphere?
There are 101,325,000 millipascals in a standard atmosphere, which is why we use this value in the formula above.
Our standard atmosphere to millipascal calculator automatically converts your pressure measurements with full decimal and scientific precision across US customary, imperial, and SI metric standards.
Atmospheres and millipascals are both units used to measure pressure. Keep reading to learn more about each unit.
What Is a Standard Atmosphere?
A standard atmosphere is a unit of pressure equal to 101,325 pascals (Pa), the base unit for pressure. Standard sea-level atmospheric pressure defined as 101,325 Pascals. [1]
The standard atmosphere is classified as a standard unit of pressure. Atmospheres can be abbreviated as atm; for example, 1 standard atmosphere can be written as 1 atm.
When working with atmospheres (atm) in formulas or technical specifications, always verify whether your target system uses SI metric, US customary, or British imperial standards.
In practice, atmospheres (atm) are widely used across large-scale industrial, bulk, and macro-level pressure specifications within international standard workflows, engineering documentation, and technical data sheets.
What Is a Millipascal?
A millipascal is a unit of pressure equal to 1/1,000 of a pascal (0.001 Pa). One-thousandth of a Pascal. [2]
The millipascal is classified as a metric and SI-compatible unit of pressure. Millipascals can be abbreviated as mPa; for example, 1 millipascal can be written as 1 mPa.
In the metric system, "milli" is the standard SI prefix for thousandths, or 10⁻³. This makes the millipascal (mPa) a convenient decimal multiple of the pascal (Pa).
In practice, millipascals (mPa) are widely used across fine-tolerance laboratory, analytical, and micro-scale pressure measurements within SI metric workflows, engineering documentation, and technical data sheets.
When converting pressure between atmospheres (atm) and millipascals (mPa), keep full floating-point precision (1 atm = 101,325,000 mPa; 1 mPa = 9.869233e-9 atm) during intermediate calculations and round only the final millipascal figure to match your instrument tolerance.
More Standard Atmosphere & Millipascal Conversions
Need to calculate in the opposite direction? Use our millipascals to atmospheres calculator to switch your starting unit immediately. You can also explore related tools such as converting millipascals to atmospheres, converting atmospheres to bars, or converting atmospheres to psi.
Convert from Atmospheres
Frequently Asked Questions
References
- [1]NIST SP 811 StandardNIST SP 811 (NIST SP 811 App. B.9 (Pressure & Stress))·Pressure Metrology Standard — Atmospheres (atm) to Millipascals (mPa)
- [2]NIST CUU SpecificationNIST CUU (Derived SI Unit: Pascal (Pa))·Unit Specifications: Standard Atmosphere (atm) & Millipascal (mPa)
- [3]BIPM ReferenceBIPM (SI Brochure (9th Ed.) — Mechanics)·Conversion Factors & Mathematical Basis (atm to mPa)