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Pascal 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

Pascal is the SI unit and the one most modern equipment specs are written in; torr is what working chemists still reach for when they talk about vacuum, especially in the low-pressure regime. A mass spectrometer ion source running at 2 × 10⁻³ Pa sits at 1.5 × 10⁻⁵ torr — same pressure, two different ways to write it. The conversion factor drops cleanly out of the atmospheric pressure equivalence: 1 atm is 760 torr and 101,325 Pa, so 1 torr is 133.322 Pa. Multiplying pascals by 0.007501 is the forward direction. Most of the time you're converting because a datasheet and a lab notebook use different conventions and you need them to agree.

Formula

torr = Pa × 0.007501

Worked Examples

101325 Pa = 760 torr

Sea-level atmospheric pressure. The anchor equivalence the factor is derived from.

133.322 Pa = 1 torr

The base conversion — 1 torr is defined as exactly 1/760 of a standard atmosphere, which works out to 133.322 Pa.

1000 Pa = 7.501 torr

A low vacuum reading — the kind of pressure a basic water aspirator or diaphragm pump can pull.

10000 Pa = 75.006 torr

Moderate vacuum, roughly where a rotary evaporator sits when pulling a low-BP solvent at reasonable bath temperatures.

Frequently Asked Questions

How do I convert pascals to torr?
Multiply by 0.007501, or equivalently divide by 133.322. So 101,325 Pa becomes 760 torr, and 1000 Pa becomes 7.5 torr. Either form works — pick whichever keeps the calculator math cleaner for your inputs.
Why does chemistry still use torr instead of pascals?
Historical inertia plus practical readability. A rotary evaporator at 10–100 torr is easier to think about than one at 1333–13,332 Pa — the torr range keeps vacuum pressures in a familiar tens to hundreds band. Modern equipment often displays both, so you can pick whichever reads more naturally for the measurement.
What's the exact definition of a torr?
1/760 of a standard atmosphere — so 101,325 / 760 = 133.32236842... Pa. The definition is exact by construction: the torr was pinned to the equivalence between atm and mmHg so the two scales come out numerically identical to within a fraction of a part per million.