What is a millitorr (mTorr)?
A millitorr (mTorr) is a unit of pressure. It equals one-thousandth of a torr. The torr comes from standard atmospheric pressure and is common in vacuum work.
What is a bar?
A bar is a metric unit of pressure. Many fields use it for weather, industrial systems, and engineering. One bar is close to normal air pressure at sea level (but not the same).
How do you convert millitorr to bar?
Use this conversion:
- bar = mTorr × 1.33322×10⁻⁶
This works because 1 torr equals about 0.00133322 bar, and 1 mTorr is 0.001 torr.
What is the conversion factor from mTorr to bar?
The conversion factor is:
- 1 mTorr = 0.00000133322 bar
- 1 mTorr = 1.33322×10⁻⁶ bar
How many millitorr are in 1 bar?
There are about:
- 1 bar = 750,061.683 mTorr
This is useful when you need to switch from bar to very low vacuum readings.
What is 1 mTorr in bar?
- 1 mTorr = 1.33322×10⁻⁶ bar
- That is 0.00000133322 bar
What is 100 mTorr in bar?
- 100 mTorr = 100 × 1.33322×10⁻⁶ bar
- 100 mTorr = 1.33322×10⁻⁴ bar
- That is 0.000133322 bar
What is 500 mTorr in bar?
- 500 mTorr = 500 × 1.33322×10⁻⁶ bar
- 500 mTorr = 6.6661×10⁻⁴ bar
- That is 0.00066661 bar
What is 760,000 mTorr in bar?
760,000 mTorr equals 760 torr (since 1,000 mTorr = 1 torr). Then:
- 760 torr ≈ 1.01325 bar
- 760,000 mTorr ≈ 1.01325 bar
This value is close to standard atmospheric pressure.
Why do vacuum systems use mTorr instead of bar?
mTorr fits low-pressure ranges better. Vacuum readings often sit far below 1 bar. Using mTorr avoids long decimals and makes changes easier to see.
Is mTorr a unit of absolute pressure?
mTorr can be used as absolute pressure, but it depends on the gauge and the setup. Many vacuum gauges report absolute pressure, while some systems reference pressure to local air pressure. Check your instrument label and method.
How do I convert mTorr to bar without scientific notation?
You can use the decimal form:
- bar = mTorr × 0.00000133322
Example:
- 250 mTorr × 0.00000133322 = 0.000333305 bar
How much should I round when converting mTorr to bar?
It depends on your use. For lab notes, 3 to 6 significant digits often works well. For tight process control, match the precision of your gauge and reporting rules.
Are torr and mTorr the same as mmHg?
They are close but not always identical in strict terms. In most vacuum and lab use, torr and mmHg are treated as equal for practical work. When you need high accuracy, use the exact definition of your standard.
What are common pressure units related to mTorr and bar?
You may also see:
- Pa (pascal)
- kPa (kilopascal)
- mbar (millibar)
- atm (atmosphere)
These units often appear in vacuum specs, pump ratings, and gas system data sheets.