How To Convert Torr to Pounds per Square Inch
Formula: psi = torr × 0.0193367747
Example: Convert 125 torr to psi.
125 × 0.0193367747 = 2.4170968375 psi
To convert manually, take your torr value and multiply it by 0.0193367747.
This gives pressure in pounds per square inch, in absolute terms.
If you need the opposite direction, divide psi by 0.0193367747 to get torr.
Quick Answer
1 torr = 0.0193367747 psi
- 10 torr = 0.193367747 psi
- 30 torr = 0.580103241 psi
- 760 torr = 14.695948772 psi
Conversion Formula
psi = torr × 0.0193367747 torr = psi ÷ 0.0193367747
This means every 1 torr is a little under 0.02 psi. The number 0.0193367747 comes from standard definitions used in science and engineering.
In more detail, it is based on these fixed reference values:
1 atm = 101,325 Pa (exact) 1 torr = 101,325 ÷ 760 Pa (exact by definition) 1 psi = 6,894.757293168 Pa (standard)
- Write down the torr value.
- Multiply it by 0.0193367747.
- The result is the pressure in psi.
Torr
A torr is a unit of pressure commonly used for vacuum measurements. It is closely related to millimeters of mercury and is used mostly in lab and vacuum work.
The torr is named after Evangelista Torricelli, who worked on early pressure experiments with mercury. Its modern definition is tied to standard atmosphere pressure, where 760 torr equals 1 atm.
Symbol: torr
- Vacuum chambers in physics and engineering
- Vacuum pumps and pump performance curves
- Freeze drying and vacuum ovens
- Thin film coating and semiconductor processes
- Plasma systems and leak testing
Pounds per Square Inch
A pound per square inch is a unit of pressure that tells how many pounds of force press on one square inch of area. It is widely used in the United States for practical pressure readings.
PSI comes from Imperial and US customary measurement systems and became popular with industrial tools and gauges. It is now a standard unit on many pressure gauges and specifications.
Symbol: psi
- Car and bike tire pressure
- Air compressors and pneumatic tools
- Hydraulic systems and jacks
- Gas cylinders and regulators
- Water pressure and pressure washers
Is this Conversion of Torr To Pounds per Square Inch Accurate?
Yes. This conversion uses standard, published definitions for pressure units. Torr is defined from standard atmosphere pressure, and psi is defined through the pascal using precise physical relationships. Because these reference values are used in textbooks, engineering work, and calibration practice, the conversion factor 1 torr = 0.0193367747 psi is reliable for study, lab work, and real world calculations.
For more details on the constants and standards behind this result, see our accuracy standards.
Real Life Examples
Here are practical cases where converting torr to psi helps you understand pressure in a unit you may see on gauges and equipment specs.
- Vacuum oven drying: A recipe calls for 50 torr. That is 0.966838735 psi absolute pressure inside the oven.
- Rough vacuum pump check: Your system reaches 10 torr at steady state. That equals 0.193367747 psi absolute.
- Deep vacuum range awareness: A chamber at 0.5 torr is at 0.00966838735 psi, which shows how tiny the pressure is compared to normal air.
- Freeze dryer pressure: A freeze dryer running at 0.1 torr is at 0.00193367747 psi absolute.
- Thin film coating process: A coating step specifies 200 torr. That is 3.86735494 psi absolute.
- Leak test comparison: A test holds at 300 torr, which equals 5.80103241 psi absolute, helpful when comparing to a psi rated gauge.
- Half atmosphere feel: 400 torr is 7.73470988 psi absolute, a bit over half of standard atmospheric pressure.
- Standard atmosphere reference: 760 torr equals 14.695948772 psi absolute, which is standard sea level atmospheric pressure in these units.
Quick Tips
- Fast mental math: psi ≈ torr ÷ 51.7149 (because 1 psi ≈ 51.7149 torr).
- Remember the anchor point: 760 torr = 14.695948772 psi.
- For rough estimates, 100 torr ≈ 1.93367747 psi.
- Be clear about gauge vs absolute: unit conversion gives absolute pressure. Many shop gauges read psig.
- Keep consistent rounding in reports, especially for lab and calibration work.
- If you convert back and forth, use the same factor 0.0193367747 to avoid drift.