Pressure Converter

Enter a pressure value and select units to convert between

Pressure Value

Convert To

Converted Pressure:

14.5038

Pound per Square Inch (PSI)

Quick Example

Scenario: A car tire pressure is 35 PSI. What is this in Bar? Result: 35 PSI ≈ 2.41 Bar.

How It Works

Enter any pressure value, select your current unit and target unit. Our tool uses precise NIST-standard conversion factors for instant, accurate calculations across all units.

Common Uses

Convert tire pressure (PSI to Bar), adjust HVAC systems, calibrate scientific instruments, calculate scuba tank pressure, and standardize engineering specifications.

Always Accessible

Works completely in your browser - no data sent to servers. Use it anytime, anywhere with full privacy protection. All calculations happen locally on your device.

How the Pressure Converter Works

Enter Your Value: Input any numerical pressure value. The tool accepts decimals, whole numbers, and scientific notation.
Select Current Unit: Choose the unit of your input value from six options: Pascal, Kilopascal, Bar, PSI, Atmosphere, or Torr.
Choose Target Unit: Select the unit you want to convert to. This can be any of the six supported pressure units.
Conversion Processing: The tool converts your input to the base unit (Pascal) first, then to your target unit using precise conversion factors.
Instant Calculation: The formula Target Value = Input Value × Conversion Factor is applied automatically.
Result Display: The converted value appears instantly with proper unit labeling and appropriate decimal precision.
Swap Functionality: Use the "Swap Units" button to instantly reverse the conversion direction without re-entering values.

Pressure Unit Definitions

Pascal (Pa)

SI unit of pressure. 1 Pa = 1 N/m². Named after Blaise Pascal. Used in scientific research and engineering calculations.

Kilopascal (kPa)

1 kPa = 1,000 Pa. Common in automotive (tire pressure), weather reporting, and medical equipment specifications.

Bar (bar)

1 bar = 100,000 Pa. Approximately atmospheric pressure at sea level. Widely used in Europe for industrial and automotive applications.

PSI (psi)

Pound per Square Inch. Imperial unit. 1 psi ≈ 6,894.76 Pa. Standard in US/UK for tire pressure, hydraulic systems, and engineering.

Atmosphere (atm)

Standard atmospheric pressure at sea level. 1 atm = 101,325 Pa = 14.6959 psi. Used in chemistry, physics, and meteorology.

Torr

1 Torr = 1/760 atm ≈ 133.322 Pa. Named after Evangelista Torricelli. Used in vacuum measurements and barometric pressure.

Step-by-Step Examples

Example 1: Car Tire Pressure

Input: 35 PSI → Convert to Bar

1. Conversion factor: 1 PSI = 0.0689476 Bar
2. Multiply: 35 × 0.0689476 = 2.413166
3. Round to practical precision: 2.41 Bar

Output: 35 PSI = 2.41 Bar

Example 2: Laboratory Pressure

Input: 0.01 atm → Convert to Torr

1. Conversion factor: 1 atm = 760 Torr (exact)
2. Multiply: 0.01 × 760 = 7.6
3. No rounding needed (exact conversion)

Output: 0.01 atm = 7.6 Torr

Practical Use Cases

Pressure conversion is essential across multiple industries and applications. Whether you're maintaining equipment, conducting experiments, or designing systems, accurate pressure unit conversion ensures safety, compliance, and optimal performance.

Automotive & Transportation

Proper tire inflation is critical for safety, fuel efficiency, and tire longevity. Mechanics and drivers regularly convert between units:

Tire Pressure: US vehicles use PSI (typically 32-35 PSI), while European cars use Bar (typically 2.2-2.4 Bar)
Engine Systems: Turbocharger boost pressure, fuel injection pressure, and hydraulic systems
Brake Systems: Hydraulic brake pressure specifications and testing
Air Suspension: Pressure settings for vehicle leveling systems

HVAC & Refrigeration

Heating, ventilation, air conditioning, and refrigeration technicians work with pressure daily:

Refrigerant Charging: Converting between PSI and Bar on manifold gauges
System Testing: Pressure testing for leaks and performance verification
Component Specifications: Compressor, valve, and pipe pressure ratings
Ductwork Design: Static pressure calculations for airflow systems

Engineering & Manufacturing

Engineers convert pressure units for design, analysis, and compliance:

Structural Design: Wind load calculations (Pa to PSF conversions)
Fluid Systems: Pipe pressure ratings, pump specifications, flow calculations
Material Testing: Stress analysis, burst pressure testing, safety factors
Quality Control: Pressure vessel testing, leak detection standards

Scientific & Medical Applications

Researchers and medical professionals require precise pressure measurements:

Laboratory Experiments: Reaction vessel pressure, vacuum systems, gas laws
Medical Devices: Blood pressure (mmHg), ventilator settings, anesthesia machines
Environmental Science: Barometric pressure tracking, weather forecasting
Scuba Diving: Tank pressure (typically Bar or PSI), depth pressure calculations

Frequently Asked Questions

What's the difference between PSI and Bar?

PSI (Pounds per Square Inch) is imperial, common in the US. Bar is metric, common in Europe. 1 bar = 14.5038 PSI. Bar is approximately equal to atmospheric pressure at sea level.

Why are there so many different pressure units?

Different industries developed their own standards historically. Torr came from mercury manometers, PSI from mechanical engineering, atm from atmospheric science, and Pascal is the modern SI unit.

How accurate is this online converter?

It uses NIST-standard conversion factors with precision suitable for engineering, automotive, and educational use. For critical applications, always verify with certified instruments.

Is Torr the same as mmHg (millimeter of mercury)?

For practical purposes, yes. 1 Torr = 1 mmHg to within 0.000015%. They are used interchangeably in medicine, meteorology, and vacuum measurements.

What is the SI unit for pressure, and should I use it?

The SI unit is Pascal (Pa). It's required in scientific publishing. For everyday use, kPa or Bar are more practical as 1 Pa is very small pressure.

Can I convert pressure for altitude with this tool?

This converts between units only. For actual atmospheric pressure at altitude, use our Altitude Pressure Calculator which accounts for elevation changes.