How to convert millimetres of mercury to kilopascals
One millimetre of mercury equals 0.133322 kilopascals, so multiply the number of millimetres of mercury by 0.133322:
kPa = mmHg × 0.133322
mmHg = kPa ÷ 0.133322 (1 kPa = 7.5006 mmHg)
Example: 80 mmHg → 80 × 0.133322 = 10.6658 kPa.
Going the other way, divide by 0.133322, or multiply by 7.5006.
Everyday values
| Millimetres of mercury | Kilopascals | For example |
|---|---|---|
| 80 mmHg | 10.6658 kPa | a normal diastolic (lower) blood pressure, roughly |
| 120 mmHg | 15.9987 kPa | a normal systolic (upper) blood pressure |
| 140 mmHg | 18.6651 kPa | a systolic value often used to define high blood pressure |
| 760 mmHg | 101.325 kPa | atmospheric pressure at sea level |
When you need this conversion
Blood pressure is measured in millimetres of mercury almost everywhere, though some scientific papers and countries use kilopascals. A reading of 120/80 mmHg is 16.0/10.7 kPa.
Millimetre of mercury to kilopascal conversion table
| mmHg | kPa | mmHg | kPa |
|---|---|---|---|
| 60 mmHg | 7.9993 kPa | 140 mmHg | 18.6651 kPa |
| 70 mmHg | 9.3326 kPa | 150 mmHg | 19.9984 kPa |
| 80 mmHg | 10.6658 kPa | 160 mmHg | 21.3316 kPa |
| 90 mmHg | 11.999 kPa | 170 mmHg | 22.6648 kPa |
| 100 mmHg | 13.3322 kPa | 180 mmHg | 23.998 kPa |
| 110 mmHg | 14.6655 kPa | 190 mmHg | 25.3313 kPa |
| 120 mmHg | 15.9987 kPa | 200 mmHg | 26.6645 kPa |
| 130 mmHg | 17.3319 kPa |
About the units
- Millimetre of mercury (mmHg): the pressure of a 1 mm column of mercury, about 133.32 Pa.
- Kilopascal (kPa): 1,000 pascals.
Both are units of pressure. The conversion factor comes from the exact definitions above, so the calculator is exact; results are only rounded for display (up to six significant digits).
Frequently asked questions
How many kilopascals are in one millimetre of mercury?
One millimetre of mercury is 0.133322 kilopascals. One kilopascal is 7.5006 millimetres of mercury.
How do I convert millimetres of mercury to kilopascals?
Multiply the value in millimetres of mercury by 0.133322. To go back, divide by 0.133322.
What is 80 mmHg in kilopascals?
80 mmHg = 10.6658 kPa.
What is 120 mmHg in kilopascals?
120 mmHg = 15.9987 kPa.
Sources
- NIST Special Publication 811 (2008), Guide for the Use of the International System of Units (SI), Appendix B: conversion factors.
- NIST Handbook 44 (2024), Appendix C: General tables of units of measurement.
Last reviewed 5 October 2026. Results are estimates; see our disclaimer.