Convert Millipascals to Standard Atmospheres
Convert Millipascals (mPa) to Standard Atmospheres (atm) instantly and accurately.
Conversion Formula
atm = mPa × 9.869232667e-9
About Millipascals
A millipascal (mPa) is 10⁻³ Pa. It appears primarily in rheology as the millipascal-second (mPa·s = centipoise) for dynamic viscosity: water at 20°C is 1.002 mPa·s; olive oil ~80 mPa·s; honey 2,000-10,000 mPa·s. Food technology, polymer processing, pharmaceutical formulation, and inkjet printing all specify flow behaviour in mPa·s. Partial pressures of trace atmospheric gases and ultra-high-vacuum leak rates measured by residual gas analysers are also expressed in millipascals. 1 mPa = 10⁻³ Pa.
About Standard Atmospheres
The standard atmosphere (atm) = exactly 101,325 Pa - defined by the 10th CGPM (1954) as the reference air pressure at sea level. Used to define STP (0°C and 1 atm) for gas law and thermochemistry. Chemical equilibrium constants (Kp), Henry's law solubility, and thermodynamic tables are tabulated at 1 atm. ISA aviation standard: sea-level 1 atm / 15°C, pressure halving every ~5.5 km. Diving physics: +1 atm per 10 m depth (fresh water) so 30 m = 4 atm absolute. Diamond formation in Earth's mantle: ~50,000 atm. 1 atm = 101,325 Pa.
Quick Reference Table
| Millipascals (mPa) | Standard Atmospheres (atm) |
|---|---|
| 1 mPa | 9.869 × 10-9 atm |
| 2 mPa | 1.974 × 10-8 atm |
| 5 mPa | 4.935 × 10-8 atm |
| 10 mPa | 9.869 × 10-8 atm |
| 25 mPa | 2.467 × 10-7 atm |
| 50 mPa | 4.935 × 10-7 atm |
| 100 mPa | 9.869 × 10-7 atm |