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Torr to Pascals Converter
↔ Convert Pa to torr instead

Common Conversions

torr Pa
0.001 0.1333
0.01 1.333
0.1 13.33
1 133.3
5 666.6
10 1333
50 6666
100 13332
200 26664
500 66661
760 101325
1000 133322

Why this conversion matters in chemistry

Vacuum gauges and surface-science instrumentation read in torr by long convention; SI-aligned facility records and physical-chemistry equations want pascals. The factor is 133.322 Pa per torr — close enough to the mmHg value to be interchangeable, since the torr is defined as exactly 1/760 of a standard atmosphere. An ultrahigh-vacuum chamber at 10⁻¹⁰ torr is 1.33 × 10⁻⁸ Pa, the value the SI-aligned data sheet would log even while the lab notebook stays in torr. Multiplying by 133.322 is the standard step that lets a vacuum reading meet a thermodynamic equation written in base SI throughout.

Formula

Pa = torr × 133.322

Worked Examples

760 torr = 101325 Pa

One standard atmosphere — the calibration anchor in both unit systems.

1 torr = 133.3 Pa

Rotary-evaporator vacuum territory for many common solvents at moderate bath temperatures.

0.01 torr = 1.333 Pa

Schlenk-line working pressure for air-sensitive chemistry — the floor a rotary-vane oil pump can comfortably reach.

23.8 torr = 3173 Pa

Water's vapor pressure at 25 °C — the value that goes into any calculation involving gas collected over water.

Frequently Asked Questions

How do I convert torr to pascals?
Multiply by 133.322. The factor falls out of 1 atm = 760 torr = 101,325 Pa, so 1 torr = 101,325 / 760 = 133.322 Pa exactly.
Why does the calculation want pascals?
The pascal is the SI base unit, and any equation using R = 8.314 J/(mol·K) needs pressures in Pa for the units to cancel cleanly into joules. ΔG = ΔG° + RT ln Q with Q expressed in pressures only behaves if those pressures are in the SI unit.
What is a pascal in base SI?
One pascal is one newton per square meter, or 1 kg/(m·s²). It's a small unit at atmospheric scale — over 100,000 of them in a standard atmosphere — which is why kPa is the working unit for most practical chemistry.
How do torr and Pa compare across vacuum levels?
Rough vacuum runs 1 to 760 torr (130 to 101,000 Pa). Medium vacuum drops to 10⁻³ to 1 torr (0.13 to 130 Pa). High vacuum goes below 10⁻³ torr (under 0.13 Pa). The torr gives more readable numbers in the low-pressure range, which is most of why it survives in surface-science work.