ATM Pressure Converter
Convert atmospheres (atm) to and from Pascals, kPa, bar, psi, mmHg, Torr, and inHg. Bidirectional conversion with preset values, reference table, and quick formulas.
mmHg to ATM Converter
Convert between millimeters of mercury (mmHg) and atmospheres with bidirectional conversion and reference pressures.
mmHg
Atmospheres (atm)⧉
0.00 atm
Converted from mmHg
Kilopascals (kPa)⧉
0.13 kPa
Converted from mmHg
Bar⧉
0.00 bar
Converted from mmHg
Pascals (Pa)⧉
133.32 Pa
Converted from mmHg
Conversion Table
| mmHg | atm | kPa | bar | Pa |
|---|---|---|---|---|
| 0.01 | 0.00 | 0.00 | 0.00 | 1.33 |
| 0.10 | 0.00 | 0.01 | 0.00 | 13.33 |
| 0.50 | 0.00 | 0.07 | 0.00 | 66.66 |
| 1.00 | 0.00 | 0.13 | 0.00 | 133.32 |
| 2.00 | 0.00 | 0.27 | 0.00 | 266.64 |
| 5.00 | 0.01 | 0.67 | 0.01 | 666.61 |
| 10.00 | 0.01 | 1.33 | 0.01 | 1,333.22 |
| 50.00 | 0.07 | 6.67 | 0.07 | 6,666.12 |
| 100.00 | 0.13 | 13.33 | 0.13 | 13,332.24 |
| 1,000.00 | 1.32 | 133.32 | 1.33 | 133,322.37 |
Quick Formulas
mmHg → atm⧉
atm = mmHg ÷ 760
Standard atmosphere relationship
atm → kPa⧉
kPa = atm × 101.325
Standard atmosphere relationship
kPa → bar⧉
bar = kPa ÷ 100
Metric pressure conversion
bar → Pa⧉
Pa = bar × 100000
Metric pressure conversion
Pa → mmHg⧉
mmHg = Pa ÷ 133.322
Conventional mmHg factor
Planning notes, formulas, and examples
About the mmHg to ATM Converter
This page converts millimeters of mercury to atmospheres and back. Even though the file path uses a shorter name, the actual unit here is mmHg, the mercury-column pressure unit used in medical and laboratory contexts.
The conversion is anchored by the standard relationship 760 mmHg = 1 atm. That makes the page useful when a blood-pressure, chamber-pressure, or mercury-column style reading needs to be compared with standard atmospheric pressure in atm. It also serves as a clean bridge for chemistry and vacuum calculations where atm is the more convenient textbook unit. In practice, that means you can move from a mercury-column reading to a standard-pressure reference without reworking the rest of the calculation. The same bridge is useful for barometric comparisons and gas-law exercises where standard atmosphere is the target unit.
Use it when you need a direct mmHg-atm conversion without bouncing through multiple pressure units first. The result is easy to compare with barometric pressure, chamber pressure, or blood-pressure style readings without mental scaling.
When This Page Helps
mmHg and atm belong to different pressure traditions but share the same atmospheric reference point. This page bridges those contexts directly and makes the 760 mmHg = 1 atm relationship easy to apply. It is useful whenever you need to compare a mercury-column reading against standard atmosphere, especially in chemistry or vacuum work.
How to Use the Inputs
- Select the input unit from the dropdown menu.
- Enter your pressure value in the input field.
- View all converted values in the output cards below.
- Use the preset buttons for common values.
- Review the conversion table for a range of values.
- Expand the reference section to see real-world pressure examples.
- Check the quick formulas for the mathematical relationships.
Formula used
ATM = mmHg ÷ 760
mmHg = ATM × 760
1 atm = 760 mmHgExample Calculation
Result: 2 atm
1,520 mmHg divided by 760 equals 2 atmospheres.
Tips & Best Practices
- 760 mmHg equals 1 atmosphere.
- 76 mmHg is 0.1 atm, which is a useful mental checkpoint.
- mmHg remains common because of mercury barometer and sphygmomanometer history.
- Atmospheres are more natural in chemistry and gas-law work.
- Torr and mmHg are very close and often treated similarly in practice.
- Always check whether the value is a medical reading, chamber reading, or barometric pressure before interpreting it.
A Mercury-Column Reference
mmHg comes from the height of a mercury column needed to balance a pressure. That history is why the unit still appears in medicine, barometry, and some laboratory equipment even though SI units are more common elsewhere.
Why Convert To Atmospheres
Atmospheres are often the cleaner unit for chemistry, gas laws, and standard-pressure comparisons. If a pressure starts in mmHg but needs to be compared with ambient conditions or textbook formulas, converting to atm is usually the quickest bridge.
Same Relationship, Different Contexts
The conversion itself is simple, but the meaning of the number depends on the setting. A medical blood-pressure reading in mmHg is not used the same way as an atmospheric or chamber pressure, even if the unit conversion is identical.
Sources & Methodology
Last updated:
Methodology
This converter first normalizes the submitted value to pascals using the unit-factor table in the page logic. It then divides by the target-unit factor to return mmHg, atm, kPa, bar, and Pa from the same base pressure value.
The mmHg↔atm relationship is anchored to the conventional standard atmosphere, so the page uses 1 atm = 760 mmHg and 1 mmHg ≈ 133.322 Pa. Display values are rounded for readability, but the same base-pressure calculation drives every converted output card and reference row.
Sources
- NIST Guide to the SI, Appendix B.8: Factors for Units Listed Alphabetically (NIST) — Includes the conventional values for atmosphere and millimeter of mercury.
Frequently Asked Questions
760 mmHg. That is the standard atmospheric reference used in chemistry, barometry, and vacuum work.
Divide mmHg by 760. For example, 380 mmHg equals 0.5 atm, which is a quick midpoint check for common pressures.
Multiply atmospheres by 760. A value of 1.25 atm therefore becomes 950 mmHg.
It remains standard in blood pressure reporting and persists in laboratory and barometric contexts because of historical mercury-column instruments. The unit is familiar to clinicians and still appears on a lot of legacy equipment.
mmHg and Torr are extremely close and are often treated as interchangeable in everyday practice. The difference is tiny enough that it rarely changes a practical result.
It means standard atmospheric pressure, which is 760 mmHg. That reference point is the baseline for many gas-law and vacuum calculations.
More in this topic
ATM to Pascals Converter
Convert between atmospheres (atm) and Pascals (Pa). Bidirectional converter with kPa, hPa, mbar, and bar outputs, reference table, and preset values.
Bar to ATM Converter
Convert between bar and atmospheres (atm) with bidirectional conversion, PSI/kPa/mmHg equivalents, reference table, and preset values.