Converter category
Pressure Converter
Convert between pascals, kilopascals, megapascals, bars, millibars, PSI, PSF, standard atmosphere, technical atmosphere, torr, mmHg, cmH₂O, inHg, and many other pressure units.
Universal Pressure Converter
About pressure conversions
Pressure conversions are essential in engineering, meteorology, medicine, automotive maintenance, and industrial processes. Our pressure converter covers SI units such as pascals, kilopascals, megapascals, and hectopascals, plus common units like bar, millibar, atmosphere, torr, and millimeters of mercury. It also includes Imperial units such as pounds per square inch, pounds per square foot, inches of mercury, and inches of water. Whether you are checking tire pressure, reading weather reports, calibrating equipment, or studying fluid mechanics, this converter provides accurate, standards-based results.
Most popular pressure conversions
Available units
Popular pressure conversions (2862 total)
Unit definitions
Pascal (Pa)
The pascal is the SI unit of pressure, defined as one newton per square meter.
Origin: Named after Blaise Pascal, French mathematician and physicist.
Current use: Scientific research, Engineering, Meteorology
Kilopascal (kPa)
A kilopascal is 1000 pascals. Used in engineering and construction.
Origin: Metric prefix kilo- denotes 1000.
Current use: Tire pressure (Europe), Engineering stress, Building codes
Megapascal (MPa)
A megapascal is 1 million pascals or about 145 psi. Used for high-pressure applications.
Origin: Metric prefix mega- denotes 1 million.
Current use: Materials testing, Hydraulic systems, Rock mechanics
Bar (bar)
A bar is 100,000 pascals, close to standard atmospheric pressure (1 atm = 1.01325 bar).
Origin: Introduced by British physicist Napier Shaw in 1909.
Current use: Meteorology, Diving, Industrial hydraulics
Millibar (mbar)
A millibar is 100 pascals. Standard unit in meteorology for atmospheric pressure.
Origin: Widely used in weather forecasting and meteorology.
Current use: Weather forecasting, Altimetry, Aviation
Pound per Square Inch (psi)
PSI is pressure from one pound-force applied to one square inch. 1 psi ≈ 6895 Pa.
Origin: Part of the Imperial/US customary system for pressure measurement.
Current use: Tire pressure, Hydraulic systems, Industrial processes
Pound per Square Foot (psf)
PSF is pressure from one pound-force on one square foot. 1 psf ≈ 47.88 Pa.
Origin: Imperial pressure unit used in US construction and engineering.
Current use: Building design (US), Wind load calculations, Floor loading
Standard Atmosphere (atm)
Standard atmosphere is defined as exactly 101,325 Pa, the average sea-level pressure.
Origin: Defined at the 10th CGPM in 1954.
Current use: Aerospace, Diving, Laboratory standards
Technical Atmosphere (at)
Technical atmosphere is pressure from 1 kgf on 1 cm². About 0.968 atm.
Origin: Used in engineering, particularly in Europe.
Current use: Engineering, Hydraulics, Old Soviet standards
Torr (Torr)
A torr is 1/760 of an atmosphere, nearly equal to 1 mmHg.
Origin: Named after Evangelista Torricelli, inventor of the barometer.
Current use: Vacuum technology, Medical vacuum, Laboratory work
Millimeter of Mercury (mmHg)
mmHg is pressure from 1mm of mercury column. Standard medical unit for blood pressure.
Origin: Derived from mercury barometer measurements.
Current use: Blood pressure, Medical equipment, Vacuum gauges
Centimeter of Water (cmH₂O)
cmH₂O is pressure from a 1 cm water column. About 98 Pa.
Origin: Used in medical equipment and respiration.
Current use: Medical ventilators, Respiratory devices, Plumbing
Inch of Mercury (inHg)
Inch of mercury is pressure from a 1-inch column of mercury. Used in aviation and weather.
Origin: Based on mercury barometer readings.
Current use: Aviation altimeters, Weather reporting, Vacuum gauges
Inch of Water (inH₂O)
Inch of water is pressure from a 1-inch water column. Used for low-pressure measurements.
Origin: Used in plumbing and HVAC applications.
Current use: HVAC, Plumbing, Medical devices
Exapascal (EPa)
1 quintillion pascals. Planetary scale.
Origin: Metric prefix exa- = 10^18.
Current use: Planetary science, Geophysics, Astrophysics
Petapascal (PPa)
Quadrillion pascals. Deep earth.
Origin: Metric prefix peta- = 10^15.
Current use: Geophysics, Deep earth, Research
Terapascal (TPa)
Trillion pascals. Industrial.
Origin: Metric prefix tera- = 10^12.
Current use: Metal forming, Industrial processes, Research
Gigapascal (GPa)
Million atmospheres. Geology.
Origin: Metric prefix giga- = 10^9.
Current use: Geology, Material science, Diamonds
Hectopascal (hPa)
100 pascals. Used for atmospheric pressure.
Origin: Meteorology standard.
Current use: Weather forecasting, Aviation, Meteorology
Decapascal (daPa)
10 pascals. Small pressure.
Origin: Metric prefix deca-.
Current use: Labs, Research
Decipascal (dPa)
0.1 pascal. Very small pressure.
Origin: Metric prefix deci-.
Current use: Acoustics, Labs
Centipascal (cPa)
0.01 pascal. Tiny pressure.
Origin: Metric prefix centi-.
Current use: Research, Microfluidics
Millipascal (mPa)
0.001 pascal. Very small.
Origin: Metric prefix milli-.
Current use: Microelectronics, Labs
Micropascal (µPa)
One millionth of a pascal.
Origin: Metric prefix micro-.
Current use: Acoustics, Seismology
Nanopascal (nPa)
One billionth of a pascal.
Origin: Metric prefix nano-.
Current use: Quantum research, Advanced physics
Picopascal (pPa)
One trillionth of a pascal.
Origin: Metric prefix pico-.
Current use: Ultralow pressure, Research
Femtopascal (fPa)
One quadrillionth of a pascal.
Origin: Metric prefix femto-.
Current use: Advanced research
Attopascal (aPa)
One quintillionth of a pascal.
Origin: Metric prefix atto-.
Current use: Fundamental physics
Newton per Square Meter (N/m²)
Same as pascal. SI pressure unit.
Origin: SI definition.
Current use: Science, Engineering
Newton per Square Centimeter (N/cm²)
10,000 pascals. 0.1 bar.
Origin: Engineering.
Current use: Materials testing, Manufacturing
Newton per Square Millimeter (N/mm²)
1 MPa. High pressure.
Origin: Engineering.
Current use: Metal forming, High pressure
Kilonewton per Square Meter (kN/m²)
1 kPa. Moderate pressure.
Origin: Engineering.
Current use: Geotechnical, Construction
Microbar (µbar)
0.1 pascal. CGS pressure.
Origin: CGS system.
Current use: Acoustics, Meteorology
Dyne per Square Centimeter (dyn/cm²)
CGS pressure = 0.1 Pa. Barye.
Origin: French CGS unit.
Current use: Physics, CGS system
Kilogram per Square Meter (kg/m²)
Pressure from 1 kg/m². 9.8 Pa.
Origin: Simple pressure.
Current use: HVAC, Clean rooms
Kilogram-force per Square Centimeter (kgf/cm²)
Technical atmosphere ≈ 1 bar.
Origin: European engineering.
Current use: German engineering, Old standards
Kilogram-force per Square Millimeter (kgf/mm²)
Very high pressure ≈ 100 atm.
Origin: High pressure.
Current use: Mining, High pressure research
Gram-force per Square Centimeter (gf/cm²)
Small pressure = 98 Pa.
Origin: Small scale.
Current use: Labs, Surface science
Ton-force per Square Foot (US) (tonf/ft²)
High US structural pressure.
Origin: Heavy construction.
Current use: US foundations, Bridges, Heavy loads
Ton-force per Square Inch (US) (tonf/in²)
Very high pressure.
Origin: Heavy engineering.
Current use: Well logging, Mining, Oil
Ton-force per Square Foot (UK) (tonf UK/ft²)
UK structural pressure.
Origin: British engineering.
Current use: UK construction, Foundations
Ton-force per Square Inch (UK) (tonf UK/in²)
Very high UK pressure.
Origin: British heavy.
Current use: UK mining, Oil
Kip per Square Inch (ksi)
1000 psi. Steel strength.
Origin: US structural.
Current use: Steel design, US construction, Materials
Pound-force per Square Foot (lbf/ft²)
47.9 Pa. Floor loading.
Origin: US building.
Current use: US floor loads, Wind load
Poundal per Square Foot (pdl/ft²)
Small Imperial pressure.
Origin: FPS system.
Current use: US physics, Education
Centimeter of Mercury (cmHg)
High pressure blood pressure.
Origin: Medical.
Current use: Blood pressure, Medical, Labs
Millimeter of Mercury (0°C) (mmHg)
Standard blood pressure mmHg.
Origin: Medical standard.
Current use: Blood pressure, Vacuum, Medical
Inch of Mercury (60°F) (inHg)
US weather pressure.
Origin: US meteorology.
Current use: US weather, Aviation (US)
Centimeter of Water (4°C) (cmH2O)
Small pressure unit.
Origin: Medical.
Current use: IV pressure, Medical devices
Millimeter of Water (mmH2O)
Very small pressure.
Origin: Clean rooms.
Current use: Clean rooms, HVAC, Labs
Inch of Water (4°C) (inH2O)
Small Imperial pressure.
Origin: US low pressure.
Current use: US HVAC, Fans
Foot of Water (4°C) (ftH2O)
Moderate Imperial pressure.
Origin: US water.
Current use: Water pressure, Diving
Inch of Water (60°F) (inH2O60)
US standard low pressure.
Origin: US industry.
Current use: US gas pressure, Ventilation
Foot of Water (60°F) (ftH2O60)
US water pressure.
Origin: US water.
Current use: US water systems, Diving
Common uses for pressure conversions
Pressure conversions are used for tire inflation, weather forecasting, blood pressure monitors, HVAC systems, hydraulics, scuba diving, and laboratory work.
Frequently asked questions about pressure
How many pascals are in 1 atmosphere?+
1 standard atmosphere equals 101,325 pascals.
What is the difference between psi and bar?+
PSI stands for pounds per square inch and is common in the US. Bar is a metric unit: 1 bar equals 100,000 pascals, or about 14.5 psi.
Which pressure units does this converter support?+
It supports SI, metric, Imperial, and specialized pressure units used in science, medicine, weather, and industry — over 50 in total.