Convert an altitude in feet or metres of height above sea level to a pressure reading in millibar (mbar, mb or mbr), pounds per square inch (psi), millimetres of mercury at zero degrees celsius (mmHg @ 0 deg C) or inches of mercury at zero degrees celsius (inHg @ 0 deg C).
Featured atmospheric pressure measurement products
DMP331 Precision Pressure Transmitter - Stainless steel pressure transmitter with ranges from 100mbar up to 40 bar gauge or absolute. Special options for ATEX , SIL2 and compound ranges.
Atmospheric air pressure transducer with 10 volt output - Pressure transducer with 0 to 10 v signal to monitor ambient air pressure in a room accurate to 0.5% range.
| ft | m | mbar | psi | mmHg | inHg |
|---|---|---|---|---|---|
| -5000 | -1524.0 | 1210.23 | 17.553 | 907.75 | 35.738 |
| -4000 | -1219.2 | 1168.55 | 16.948 | 876.48 | 34.507 |
| -3000 | -914.40 | 1128.03 | 16.361 | 846.09 | 33.311 |
| -2000 | -609.60 | 1088.66 | 15.790 | 816.56 | 32.148 |
| -1000 | -304.80 | 1050.41 | 15.235 | 787.87 | 31.018 |
| -900 | -274.32 | 1046.64 | 15.180 | 785.05 | 30.907 |
| -800 | -243.84 | 1042.89 | 15.126 | 782.23 | 30.796 |
| -700 | -213.36 | 1039.15 | 15.072 | 779.42 | 30.686 |
| -600 | -182.88 | 1035.41 | 15.017 | 776.62 | 30.576 |
| -500 | -152.40 | 1031.69 | 14.963 | 773.83 | 30.466 |
| -400 | -121.92 | 1027.98 | 14.910 | 771.05 | 30.356 |
| -300 | -91.440 | 1024.28 | 14.856 | 768.28 | 30.247 |
| -200 | -60.960 | 1020.59 | 14.802 | 765.51 | 30.138 |
| -100 | -30.480 | 1016.92 | 14.749 | 762.75 | 30.030 |
| -50 | -15.240 | 1015.08 | 14.723 | 761.37 | 29.975 |
| 0 | 0 | 1013.25 | 14.696 | 760.00 | 29.921 |
| 50 | 15.240 | 1011.42 | 14.669 | 758.63 | 29.867 |
| 100 | 30.480 | 1009.59 | 14.643 | 757.26 | 29.813 |
| 200 | 60.960 | 1005.95 | 14.590 | 754.52 | 29.706 |
| 300 | 91.440 | 1002.31 | 14.537 | 751.80 | 29.598 |
| 400 | 121.92 | 998.689 | 14.485 | 749.08 | 29.491 |
| 500 | 152.40 | 995.075 | 14.432 | 746.37 | 29.385 |
| 600 | 182.88 | 991.472 | 14.380 | 743.67 | 29.278 |
| 700 | 213.36 | 987.880 | 14.328 | 740.97 | 29.172 |
| 800 | 243.84 | 984.298 | 14.276 | 738.28 | 29.066 |
| 900 | 274.32 | 980.727 | 14.224 | 735.61 | 28.961 |
| 1000 | 304.80 | 977.166 | 14.173 | 732.93 | 28.856 |
| 2000 | 609.60 | 942.129 | 13.664 | 706.65 | 27.821 |
| 3000 | 914.40 | 908.117 | 13.171 | 681.14 | 26.817 |
| 4000 | 1219.2 | 875.105 | 12.692 | 656.38 | 25.842 |
| 5000 | 1524.0 | 843.073 | 12.228 | 632.36 | 24.896 |
| 6000 | 1828.8 | 811.996 | 11.777 | 609.05 | 23.978 |
| 7000 | 2133.6 | 781.854 | 11.340 | 586.44 | 23.088 |
| 8000 | 2438.4 | 752.624 | 10.916 | 564.51 | 22.225 |
| 9000 | 2743.2 | 724.285 | 10.505 | 543.26 | 21.388 |
| 10000 | 3048.0 | 696.817 | 10.106 | 522.66 | 20.577 |
| 15000 | 4572.0 | 571.820 | 8.2935 | 428.90 | 16.886 |
| 20000 | 6096.0 | 465.633 | 6.7534 | 349.25 | 13.750 |
| 25000 | 7620.0 | 376.009 | 5.4536 | 282.03 | 11.104 |
| 30000 | 9144.0 | 300.896 | 4.3641 | 225.69 | 8.8855 |
| 35000 | 10668 | 238.423 | 3.4580 | 178.83 | 7.0406 |
| 40000 | 12192 | 187.54 | 2.7200 | 140.67 | 5.5381 |
| 45000 | 13716 | 147.48 | 2.1390 | 110.62 | 4.3550 |
| 50000 | 15240 | 115.97 | 1.6821 | 86.987 | 3.4247 |
| 55000 | 16764 | 91.199 | 1.3227 | 68.405 | 2.6931 |
| 60000 | 18288 | 71.717 | 1.0402 | 53.792 | 2.1178 |
| 65000 | 19812 | 56.397 | 0.8180 | 42.301 | 1.6654 |
| 70000 | 21336 | 44.377 | 0.6436 | 33.286 | 1.3105 |
| 75000 | 22860 | 34.978 | 0.5073 | 26.236 | 1.0329 |
| 80000 | 24384 | 27.615 | 0.4005 | 20.713 | 0.8155 |
| 85000 | 25908 | 21.837 | 0.3167 | 16.379 | 0.6448 |
| 90000 | 27432 | 17.296 | 0.2509 | 12.973 | 0.5107 |
| 95000 | 28956 | 13.721 | 0.1990 | 10.291 | 0.4052 |
| 100000 | 30480 | 10.902 | 0.1581 | 8.1769 | 0.3219 |
Featured vacuum range absolute pressure measurement products
Vacuum digital gauge to measure 0 to 1000 mbar absolute - We have a need for a general vacuum digital gauge which can display 0-1000mbar vacuum as absolute readings. 
DMP457 Marine Approved Pressure Transmitter - Marine approved stainless steel diaphragm pressure transmitter with 4-20mA current loop output for shipbuilding in ranges from 100mb to 600 bar gauge or absolute.
The height relative to sea level conversions are derived using the US Standard Atmosphere 1976 barometric formula for geopotential altitude with the following values[1-6] at heights from 5,000 ft (1524 m) below to 100,000 ft (30,480 m) above mean sea level.
- Standard atmospheric pressure of 1013.25 mb at 0 m, 226.321 mb at 11,000 m, 54.7489 mb at 20,000 m above mean sea level.
- Standard temperature of 288.15K (15°C) at 0 m, 216.65K (-56.5°C) at 11,000 m and 20,000 m above mean sea level.
- Standard thermal gradient or lapse rate of -0.0065 K/m from 0 to 11,000 m, 0 K/m from 11,000 to 20,000 m, 0.001 k/m from 20,000 to 32,000 m above mean sea level.
- Standard acceleration due to gravity of 9.80665 m/s².
- Gas constant for air of 8.31432 J/Kmol K.
- Molar mass of air of 0.0289644 kg/mole.
n.b. Please note that the calculated altitude values are not absolute precise conversions and should not be treated as such.
Featured atmospheric pressure measurement products
- Marine approved atmospheric pressure sensor - Marine-approved pressure sensor for atmospheric pressure measurement on ships. 4-20mA output, 800-1200mbar range.
- Barometric Pressure Transmitters - Select barometric pressure transmitters with compressed output scaling for superior resolution in detecting incremental atmospheric changes. Ideal for environmental controls & gas analysis compensation.