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Vacuum - Pressure Units Converter

The table below can be used to convert between commonly used vacuum units:

Vacuum - Equivalent Pressure Units Converter
%
Vacuum
Torr
(mm Mercury)
Micronpsia,
(lb/in2
abs)
Inches
Mercury
Absolute
Inches
Mercury
Gauge
kPa
abs
0.0 760.0 760,000 14.7 29.92 0.00 101.4
1.3 750.0 750,000 14.5 29.5 0.42 99.9
1.9 735.6 735,600 14.2 28.9 1.02 97.7
7.9 700.0 700,000 13.5 27.6 2.32 93.5
21.0 600.0 600,000 11.6 23.6 6.32 79.9
34.0 500.0 500,000 9.7 19.7 10.22 66.7
47.0 400.0 400,000 7.7 15.7 14.22 53.2
50.0 380.0 380,000 7.3 15.0 14.92 50.8
61.0 300.0 300,000 5.8 11.8 18.12 40
74.0 200.0 200,000 3.9 7.85 22.07 26.6
87.0 100.0 100,000 1.93 3.94 25.98 13.3
88.0 90.0 90,000 1.74 3.54 26.38 12
89.5 80.0 80,000 1.55 3.15 26.77 10.7
90.8 70.0 70,000 1.35 2.76 27.16 9.3
92.1 60.0 60,000 1.16 2.36 27.56 8
93.0 51.7 51,700 1.00 2.03 27.89 6.9
93.5 50.0 50,000 0.97 1.97 27.95 6.7
94.8 40.0 40,000 0.77 1.57 28.35 5.3
96.1 30.0 30,000 0.58 1.18 28.74 4
96.6 25.4 25,400 0.49 1.00 28.92 3.4
97.4 20.0 20,000 0.39 0.785 29.14 2.7
98.7 10.0 10,000 0.193 0.394 29.53 1.3
99.0 7.6 7,600 0.147 0.299 29.62 1.0
99.87 1.0 1,000 0.01934 0.03937 29.88 0.13
99.90 0.75 750 0.0145 0.0295 29.89 0.1
99.99 0.10 100 0.00193 0.00394 29.916 0.013
99.999 0.01 10 0.000193 0.000394 29.9196 0.0013
100 0.00 0 0 0 29.92 0
  • 1 psi (lb/in2) = 6,894.8 Pa (N/m2) = 6.895×10-3 N/mm2 = 6.895×10-2 bar

Download and print Vacuum Units Converter Chart

Convert from % Vacuum to Unit of Pressure

The % of vacuum is a relative value where pressure at normal or standard atmosphere is the base value.

pv% = 100% - (pv / patm) 100%                                       (1)

where

pv% = vacuum (%)

pv = absolute pressure (psia, kPa, bar ..)

patm = absolute presure at normal or standard conditions (psia, kPa, bar ..)

Example - Pressure in kPa and % Vacuum

The vacuum with absolute pressure 4 kPa and standard pressure 101.4 kPa can be calculated as

pv% = 100% - ((4 kPa) / (101.4 kPa)) 100% 

       = 96.1 %

Example - Pressure in kPa and % Vacuum

The vacuum with absolute pressure 0.1 bar and standard pressure 1 bar can be calculated as

pv% = 100% - ((0.1 bar) / (1 bar)) 100% 

       = 90 %

Vacuum Ranges

Vacuum Ranges
Pressure
(Pa)
Low vacuum 1×105 to 3×103
Medium vacuum 3×103 to 1×10-1
High vacuum 1×10-1 to 1×10-7
Ultra high vacuum 1×10-7 to 1×10-10
Extremely high vacuum 1×10-10
Perfect vacuum 0
  • Outer space 1×10-4 to < 3×10-15

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