How many torrs are in 1 psi?

1 psi equals 51.71493257 torrs, using the exact defined conversion factor rather than an estimate.

How do I convert psi to torr?

Multiply the psi value by 51.71493257. The converter above does this instantly to whatever precision you set.

How do I convert torr back to psi?

Use the reverse factor: 1 torr equals 0.0193367747 psi. You can also use the swap control in the converter above to flip the direction instantly.

Torr (Torr) is a unit of pressure.

Is the psi to torr 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 Torrs 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 Torrs

PSI and Torr 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

torrs = psi × 51.7149325715

This factor comes from each unit's defined relationship to the category's base unit: 1 psi equals 6894.75729317 base units, and 1 torr equals 133.322368421 base units, so dividing one by the other gives the direct psi-to-torr factor of 51.7149325715.

Simple example

1 psi × 51.71493257 = 51.71493257 Torr

1 psi = 51.71493257 torrs.

Real-world example

35 psi × 51.71493257 = 1,810.02264 Torr

35 psi = 1,810.02264 torrs.

Conversion table

PSI (psi)	Torr (Torr)
1 psi	51.71493257 Torr
5 psi	258.5746629 Torr
10 psi	517.1493257 Torr
25 psi	1,292.873314 Torr
50 psi	2,585.746629 Torr
100 psi	5,171.493257 Torr

Reverse conversion: Torr to PSI

51.71493257 Torr × 0.0193367747 = 1 psi

51.71493257 torrs = 1 psi.

psi = torrs × 0.0193367747046

For a page dedicated to this direction, see Torr 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 Torr (Torr)

A torr is 1/760 standard atmosphere.

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 Torrs Converter — psi to Torr

Pressure Converter