Pressure Converter (All-in-One)
Convert between Pascal, bar, psi, atm, torr and more instantly
Converted Values
Pascal (Pa): 1.00
Kilopascal (kPa): 0.00
Bar: 0.00
PSI: 0.00
Atmosphere (atm): 0.00
Torr: 0.01
Formula
All conversions are based on Pascal (Pa) as the base unit.
Example: 1 bar = 100,000 Pa
1 atm = 101,325 Pa
What Is the Pressure Converter (All-in-One)?
Pressure is force distributed over an area, and the pascal (Pa) — one newton of force per square meter — is its SI unit. This converter takes a single pressure value and instantly shows it in Pascal, kilopascal, bar, PSI, atmosphere, and torr at the same time, so you don't have to look up or calculate each conversion factor separately.
The pascal itself is a relatively young unit name: the 14th General Conference on Weights and Measures adopted it in 1971, honoring 17th-century French scientist Blaise Pascal, whose experiments with barometers helped establish how fluid pressure behaves. Older units survived alongside it for practical reasons — the bar stuck around in meteorology and diving because it sits close to everyday atmospheric pressure, PSI (pounds per square inch) became the US standard for tires and hydraulics, and torr, named after Italian physicist Evangelista Torricelli who built the first mercury barometer in 1643, is still used in vacuum science because it maps directly onto millimeters of mercury.
Pressure conversions also matter whenever gas behavior is involved, since pressure, volume, and temperature are linked by the gas laws — see the Temperature Converter and Volume Converter for the other two variables in that relationship.
Pressure Converter (All-in-One) Formula
- 1 bar = 100,000 Pa
- 1 atm = 101,325 Pa
- 1 psi = 6,894.76 Pa
- 1 torr = 133.322 Pa
How Is the Pressure Converter (All-in-One) Calculated?
The Pascal is the SI base unit of pressure, defined as one newton of force per square meter — a genuinely small unit of everyday pressure, which is why kilopascals (kPa) are more commonly quoted in weather reports and engineering specs. Every other unit here converts to Pascal by a fixed multiplication factor: bar was chosen as close to standard atmospheric pressure for convenience (1 bar = 100,000 Pa exactly, by definition), atm is fixed at exactly 101,325 Pa to represent average sea-level pressure, and PSI derives from the imperial pound-force and square inch (1 psi ≈ 6,894.76 Pa).
Torr is defined as 1/760 of a standard atmosphere (101,325 / 760 = 133.322… Pa), a figure that traces directly back to mercury barometer readings, where 760 mm of mercury column height at sea level balances the weight of the atmosphere above it. Because every factor here is a straight multiplier with no offset (unlike temperature), converting between any two pressure units is always a single multiplication or division through Pascal as the common base.
Pressure Converter (All-in-One) Example
A car tire inflated to 32 PSI converts to 32 × 6,894.76 = 220,632 Pa (220.63 kPa), or 220,632 / 100,000 = 2.21 bar, or 220,632 / 101,325 ≈ 2.18 atm.
Standard atmospheric pressure, 1 atm, equals exactly 101,325 Pa (101.325 kPa), 1.01325 bar, about 14.70 PSI, and exactly 760 torr by definition.
A home espresso machine running at 9 bar equals 9 × 100,000 = 900,000 Pa (900 kPa), 900,000 / 6,894.76 ≈ 130.53 PSI, and 900,000 / 101,325 ≈ 8.88 atm — nearly nine times sea-level atmospheric pressure.
How to Use the Pressure Converter (All-in-One)
Step 1
Enter a pressure value.
Step 2
Select the unit you're starting from.
Step 3
View the converted pressure across all six supported units instantly.
Step 4
Compare the kPa or bar figure against a spec sheet if you're checking equipment or tire pressure.
Step 5
Adjust the input and watch every unit update together to build intuition for how the units relate.
Step 6
Use the atm or torr values directly if you're working through a chemistry or vacuum-science problem.
Benefits
- Converts six units — Pa, kPa, bar, PSI, atm, and torr — from a single input, all at once.
- Bridges scientific (Pa), automotive (PSI), and meteorological (atm) pressure units.
- Removes the need to memorize or look up six different conversion factors.
- Useful for tire pressure, weather, cooking (pressure cookers), and engineering conversions alike.
- Runs instantly in your browser with no signup, and results can be printed or shared as a branded image.
- Uses exact, standard-definition conversion factors rather than rounded approximations.
Common Pressure Converter (All-in-One) Scenarios
Scenario 1
Converting tire pressure specs between PSI and bar when buying tires abroad or reading an imported vehicle manual.
Scenario 2
Understanding barometric pressure readings in hPa/kPa versus the inHg or atm units used elsewhere.
Scenario 3
Physics and engineering coursework involving pressure calculations across unit systems.
Scenario 4
Checking scuba diving tank or regulator pressure ratings, often specified in bar or PSI depending on manufacturer.
Scenario 5
Interpreting industrial equipment gauges and datasheets that mix Pascal-based SI units with PSI.
Scenario 6
Understanding pressure cooker or espresso machine bar ratings against more familiar units.
Understanding Your Result
Each figure in the results represents the exact same physical pressure, expressed in a unit common to its typical field — Pascals and kilopascals in science and engineering, PSI in US automotive contexts, and atm or torr in chemistry, meteorology, and vacuum work. None of the six values is more "correct" than another; they're just different scales for describing the same force-per-area.
For a quick sense of scale: a typical car tire runs 28–35 PSI (about 1.9–2.4 bar), standard sea-level atmospheric pressure is 1 atm (101,325 Pa, or 760 torr), and a household pressure cooker typically operates around 1 bar above atmospheric (roughly 15 PSI gauge). Deep vacuum systems, by contrast, are often measured in millitorr — small fractions of a single torr.
Tips
- Check your vehicle's manual for the correct tire PSI before inflating — don't rely on the number printed on the tire's sidewall, which is a maximum, not a recommendation.
- Use bar or kPa for most international pressure specifications outside the US.
- Remember standard atmospheric pressure is defined as exactly 1 atm (101,325 Pa, 760 torr).
- For vacuum work, look at the torr or millitorr figure rather than converting through PSI, which is too coarse at that scale.
- When comparing pressure cooker or espresso machine ratings, confirm whether the bar figure is gauge (above atmosphere) or absolute.
Common Mistakes
- Confusing gauge pressure (relative to atmosphere) with absolute pressure — this converter handles raw values, not the distinction between them.
- Mixing up bar and PSI, which differ by roughly a factor of 14.5.
- Using an outdated or region-specific tire pressure figure instead of the vehicle manufacturer's spec.
- Assuming 1 bar and 1 atm are identical — they're close (1 bar ≈ 0.987 atm) but not exactly equal.
- Reading a barometric pressure report in hPa as if it were kPa — 1 hPa = 0.1 kPa, a tenfold difference if missed.
Frequently Asked Questions
What is a Pascal?
The Pascal (Pa) is the SI unit of pressure, defined as one newton of force per square meter. It was adopted as the SI unit name in 1971, honoring physicist Blaise Pascal, though it's such a small unit that kilopascals are more commonly used in practice.
How do I convert PSI to bar?
Divide the PSI value by 14.5038 to get the equivalent in bar — for example, 30 PSI ÷ 14.5038 ≈ 2.07 bar.
Where is a pressure converter commonly used?
It's used in engineering, meteorology (barometric pressure), tire pressure checks, scuba diving, cooking (pressure cookers and espresso machines), and industrial process monitoring.
What is standard atmospheric pressure?
Standard atmospheric pressure at sea level is defined as exactly 1 atm, which equals 101,325 Pa, 101.325 kPa, about 14.7 PSI, or exactly 760 torr.
What is torr used for?
Torr is commonly used in vacuum technology and some scientific fields, historically based on the height of a mercury column in a barometer — it's named after Evangelista Torricelli, who built the first mercury barometer in 1643.
Why do tire gauges show PSI in some countries and bar in others?
PSI is the standard automotive pressure unit in the US, while most other countries use bar or kPa, reflecting broader metric vs. imperial system preferences.
Why do different countries use different pressure units for tires?
It largely follows each country's broader measurement system convention — PSI is standard in the US, while bar or kPa is more common in most of Europe and many other regions.
What is gauge pressure versus absolute pressure?
Gauge pressure measures relative to atmospheric pressure (what most everyday tools like tire gauges show), while absolute pressure measures from a true vacuum (zero) — most consumer measurements are gauge pressure.
How is atmospheric pressure related to weather forecasting?
Falling atmospheric pressure often signals incoming stormy weather, while rising pressure typically indicates clearing, stable conditions — meteorologists track pressure changes as a key forecasting tool, usually reported in hectopascals (hPa).
Can I share this conversion as an image?
Yes — tap Share and, on supported devices, your conversion is shared as a branded image card, not just a text link.
Why is bar not an official SI unit even though it's widely used?
Bar was defined before the SI system was formalized and kept for practical convenience since it's so close to atmospheric pressure, but the SI-coherent unit remains the Pascal — bar is accepted for use alongside SI, not part of it.
How many PSI is a home pressure cooker?
Most household pressure cookers operate around 1 bar of gauge pressure above atmospheric, which is roughly 14.5–15 PSI — enough to raise water's boiling point and cook food faster.
Is kPa or hPa more common in weather reports?
Meteorologists most often report barometric pressure in hectopascals (hPa), which are numerically identical to the older unit millibar — 1 hPa = 0.1 kPa, so a reading of 1013 hPa equals 101.3 kPa.
Why does scuba diving gear list pressure in bar?
Diving tanks and regulators are commonly rated in bar internationally (and PSI in the US) because bar conveniently approximates atmospheric pressure, making it easy to reason about pressure changes with depth underwater.
References
Important Information
All conversions are exact based on standard unit definitions.
Last updated: July 25, 2026