kPa to mmHg Conversion Calculator
Convert kilopascal to millimeters of mercury instantly, both directions, with adjustable precision. This free kPa to mmHg calculator also converts mmHg to kPa, kPa to torr, and covers psi, bar, atm, and Pa, with a conversion chart, table, formula, and blood pressure reference. To convert mmHg to kPa, select mmHg as the source unit or tap the swap button.
Live Converter
kPa to mmHg Conversion Formula
mmHg = kPa x 7.5006168270417
kPa = mmHg x 0.1333223684211
Exact forms: mmHg = kPa x (760 / 101.325); kPa = mmHg x (101.325 / 760). The anchor is standard atmospheric pressure: 101.325 kPa = 760 mmHg exactly. One torr equals one mmHg by convention, so the kPa to torr factor is identical. This exact kPa to mmHg formula is used for every calculation on this page; the kilopascal to mmHg factor is 760/101.325.
kPa to mmHg Chart (Quick Table)
| kPa | mmHg | kPa | mmHg |
|---|
Use this kPa to mmHg table as a quick chart for common values from 1 to 500. Values rounded to 4 decimals. The highlighted row is standard atmospheric pressure: 101.325 kPa = 760 mmHg exactly.
Pressure Context Cards
Blood Pressure
A reading of 120/80 mmHg equals 15.9987 / 10.6658 kPa. Clinicians use mmHg almost everywhere; some devices and countries (parts of Europe, Australia) report kPa instead.
Atmospheric Pressure
Standard atmosphere: 101.325 kPa = 760 mmHg. Weather stations often report hectopascals: 1 hPa = 0.1 kPa = 0.7501 mmHg.
Tire Pressure
Typical car tire: 32 psi = 220.6322 kPa = 1654.8778 mmHg. Common range 30-35 psi equals 206.8427-241.3165 kPa.
Vacuum
Perfect vacuum is 0 kPa = 0 mmHg absolute. A rough vacuum of 10 kPa absolute equals 75.0062 mmHg absolute. Minus 50 kPa gauge equals 51.325 kPa absolute = 384.9692 mmHg absolute.
mmHg vs Torr: Convention and Exact Definitions
| Unit | Exact definition | In pascals |
|---|---|---|
| mmHg (conventional) | 101325/760 Pa | 133.3223684211 |
| torr | 101325/760 Pa | 133.3223684211 |
| kPa | 1000 Pa | 1000 |
| atm | 101325 Pa | 101325 |
You may also see 1 mmHg quoted as 133.322387415 Pa. That is an older conventional figure; the exact-by-definition value derived from 1 atm = 760 mmHg is 101325/760 = 133.3223684211 Pa, a difference of about 0.0000143 percent. This tool uses the exact definition, which is also why 101.325 kPa converts to exactly 760 mmHg.
Worked Examples
Common lookups: 100 kPa to mmHg = 750.0617 mmHg, 50 kPa to mmHg = 375.0308 mmHg, and 200 kPa to mmHg = 1500.1234 mmHg.
Frequently Asked Questions
What is the formula to convert kPa to mmHg?
Multiply kilopascals by 7.5006168270417 to get millimeters of mercury. The exact formula is mmHg = kPa x (760 / 101.325), because standard atmospheric pressure is defined as exactly 101.325 kPa = 760 mmHg.
How do you convert mmHg back to kPa?
Multiply millimeters of mercury by 0.1333223684211 to get kilopascals. The exact formula is kPa = mmHg x (101.325 / 760), which is the reciprocal of the kPa to mmHg factor.
What is 101.325 kPa in mmHg?
101.325 kPa is exactly 760 mmHg. This is the definition of standard atmospheric pressure, so it is the most important anchor point for this conversion.
What is 100 kPa in mmHg?
100 kPa equals 750.0617 mmHg (100 x 7.5006168270417). This is a common reference point just below one standard atmosphere.
What is 50 kPa in mmHg?
50 kPa equals 375.0308 mmHg. This is roughly half of one standard atmosphere.
What is 200 kPa in mmHg?
200 kPa equals 1500.1234 mmHg, which is about 1.97 standard atmospheres.
What is 120 mmHg in kPa?
120 mmHg equals 15.9987 kPa. A normal systolic blood pressure reading of 120 mmHg converts to about 16.0 kPa.
Is 1 torr the same as 1 mmHg?
For all practical purposes, yes. One torr is defined as exactly 101325/760 pascals, which differs from the conventional mmHg definition by only about 0.0000143 percent. This converter treats them as identical.
Why is blood pressure measured in mmHg instead of kPa?
Blood pressure is measured in mmHg because of the historical mercury sphygmomanometer, and the unit stuck in clinical practice. Some countries and devices report kPa instead, where a normal reading of 120/80 mmHg becomes about 16.0/10.7 kPa.
How do I convert kPa to torr?
Use the same factor as for mmHg: torr = kPa x 7.5006168270417. One torr equals one mmHg by convention, so 100 kPa equals 750.0617 torr.
How do I convert psi to mmHg?
Convert psi to kPa first (1 psi = 6.894757293168 kPa), then to mmHg. Combined: mmHg = psi x 51.71493257. For example, 32 psi equals 1654.8778 mmHg.
What is normal car tire pressure in kPa and mmHg?
A typical car tire pressure of 32 psi equals 220.6322 kPa, which equals 1654.8778 mmHg. Always follow the pressure listed on the driver side door placard, not the maximum printed on the tire.
What is a perfect vacuum in kPa and mmHg?
A perfect vacuum is 0 kPa absolute, which is 0 mmHg absolute. Vacuum gauges often read in negative kPa relative to atmosphere, so minus 50 kPa gauge equals 51.325 kPa absolute, or 384.9692 mmHg absolute.
How many decimal places should I use for kPa to mmHg?
Four decimal places (for example 750.0617) are enough for almost every practical use. This converter lets you adjust precision from 0 to 10 decimals.
Can I use this converter for medical blood pressure readings?
This converter is an educational reference tool, not a medical device. Conversion math is exact, but always rely on your blood pressure monitor and your doctor for health decisions, not on a unit conversion.
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