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Pascals to Torr Converter
↔ Convert torr to Pa instead

Common Conversions

Pa torr
1 0.007501
10 0.075006
100 0.750062
133.322 1
500 3.75
1000 7.501
5000 37.503
10000 75.006
50000 375.031
100000 750.062
101325 760
200000 1500.12

Why this conversion matters in chemistry

If you spend any time around vacuum lines, mass spectrometers, or thin-film deposition systems, you end up swapping between pascals and torr constantly — pascal is what the gauge displays in SI mode, torr is what the protocol was written in twenty years ago. The factor that bridges them comes straight out of the atmospheric equivalence: 1 atm is 760 torr and 101,325 Pa, so 1 torr is exactly 101,325/760 = 133.322 Pa. Going from pascals to torr is the division — divide Pa by 133.322, or equivalently multiply by 0.007501. A 5 Pa reading on a Schlenk-line gauge becomes 0.0375 torr, which is the same pressure expressed in the units the rotary-vane pump's spec sheet uses. The arithmetic is trivial; the awkward part is just remembering which way the factor runs.

Formula

torr = Pa ÷ 133.322

Worked Examples

101325 Pa = 760 torr

One standard atmosphere. The defining equivalence the conversion factor is built on.

133.322 Pa = 1 torr

The base ratio. Useful as a sanity check — if your conversion doesn't reduce 133 Pa to roughly 1 torr, the factor went the wrong direction.

13332 Pa = 100 torr

Typical rotary-evaporator working pressure. Low enough to drive most organic solvents off near room temperature.

5 Pa = 0.0375 torr

A respectable Schlenk-line vacuum — well into the regime where air-sensitive transfers are safe.

Frequently Asked Questions

How do I convert pascals to torr?
Divide by 133.322, or multiply by 0.007501. Either form gives the same answer — 13,332 Pa lands at 100 torr, 5 Pa lands at 0.0375 torr. Pick whichever keeps your calculator math cleaner; with most vacuum readings you're dividing a large pascal number, so the divide form tends to feel more natural.
Is torr the same thing as mmHg?
Practically yes, to within a few parts per million. Both pin themselves to the same atmospheric anchor (760 of the unit equals 1 atm), but mmHg is defined in terms of an actual mercury column at standard conditions, while torr was redefined in 1985 to be exactly 1/760 of an atmosphere. The two read identically for almost any chemistry application.
Why does vacuum work still report in torr if pascals are SI?
The equipment ecosystem grew up in torr. Most pump spec sheets, vacuum-gauge manuals, and protocols from before the SI push are written in torr, and the working ranges (10⁻³ to 10² torr for rough/medium vacuum) sit at convenient single- and double-digit numbers. Pascals push the same readings into awkward thousands and tens of thousands, so torr stuck around for readability.