How many millipascals are in 1 psi?

1 psi equals 6,894,757.293 millipascals, using the exact defined conversion factor rather than an estimate.

How do I convert psi to millipascal?

Multiply the psi value by 6894757.293. The converter above does this instantly to whatever precision you set.

How do I convert millipascal back to psi?

Use the reverse factor: 1 millipascal equals 1.450377e-7 psi. You can also use the swap control in the converter above to flip the direction instantly.

What is a millipascal?

Millipascal (mPa) is a unit of pressure.

Is the psi to millipascal conversion exact?

Yes. PSI (pounds-force per square inch) equals exactly 6,894.757293168 pascals. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.

PSI to Millipascals Converter

Q: What is a psi?

PSI (psi) measures pressure. PSI (pounds-force per square inch) equals exactly 6,894.757293168 pascals. It is classified as a US/imperial customary unit.

About Converting PSI to Millipascals

PSI and Millipascal both show up on pressure gauges — psi is standard on US tire and tool specifications, while bar is the everyday pressure unit across most of the rest of the world. PSI is most often used for tire pressure specifications in the us.

Formula

millipascals = psi × 6894757.29317

This factor comes from each unit's defined relationship to the category's base unit: 1 psi equals 6894.75729317 base units, and 1 millipascal equals 0.001 base units, so dividing one by the other gives the direct psi-to-millipascal factor of 6894757.29317.

Simple example

1 psi × 6894757.293 = 6,894,757.293 mPa

1 psi = 6,894,757.293 millipascals.

Real-world example

35 psi × 6894757.293 = 241,316,505.3 mPa

35 psi = 241,316,505.3 millipascals.

Conversion table

PSI (psi)	Millipascal (mPa)
1 psi	6,894,757.293 mPa
5 psi	34,473,786.47 mPa
10 psi	68,947,572.93 mPa
25 psi	172,368,932.3 mPa
50 psi	344,737,864.7 mPa
100 psi	689,475,729.3 mPa

Reverse conversion: Millipascal to PSI

1 mPa × 1.450377e-7 = 1.450377e-7 psi

1 millipascal = 1.450377e-7 psi.

psi = millipascals × 1.450377e-7

For a page dedicated to this direction, see Millipascal to PSI.

Understanding the PSI

PSI (psi) measures pressure. PSI (pounds-force per square inch) equals exactly 6,894.757293168 pascals. It is classified as a US/imperial customary unit.

Where it's used: United States (standard pressure unit for tires, tools, and plumbing)

Uses of the PSI today

Tire pressure specifications in the US
Hydraulic and pneumatic system ratings
Plumbing, compressed-air tools, and industrial equipment ratings

History of the PSI

PSI is a derived unit from the pound-force and the inch, both themselves standardized through English and later international agreements rather than invented as a pressure unit from scratch.

It became the default pressure unit in US engineering as pound-force and inch-based measurement dominated American industry through the 19th and 20th centuries, and it remains in everyday use for tires and tools even as most other measurements in the US context stay imperial.

Historical origin. PSI was not the invention of a single named person; it developed through the process described above.

Understanding the Millipascal (mPa)

Millipascal is 0.001 pascal units.

PSI — sources

NIST Special Publication 811 — Guide for the Use of the International System of Units — Documents conversion factors for psi and other US customary pressure units.

PSI to Millipascals Converter — psi to mPa

Pressure Converter