Common Pressure Conversions
About Pressure Conversion
Convert between different units of pressure including pascal, bar, psi, atmosphere, and more. Essential for engineering, meteorology, and scientific applications.
Frequently Asked Questions
What is atmospheric pressure and why does it vary?
Standard atmospheric pressure is 101.325 kPa (14.7 psi) at sea level. It decreases with altitude and varies with weather patterns. High pressure systems bring clear weather, while low pressure brings storms.
How do I convert between psi and bar?
1 bar = 14.504 psi, and 1 psi = 0.0689 bar. Bar is commonly used in Europe and scientific contexts, while psi is standard in the US for tire pressure, hydraulics, and pneumatics.
What tire pressure should I use?
Check your vehicle's door jamb or manual for recommended tire pressure, typically 30-35 psi (2.1-2.4 bar). Proper pressure improves fuel economy, tire life, and safety. Check when tires are cold.
What's the difference between gauge and absolute pressure?
Gauge pressure measures relative to atmospheric pressure (tire pressure gauges), while absolute pressure includes atmospheric pressure. Absolute pressure = gauge pressure + atmospheric pressure.
How is blood pressure measured?
Blood pressure is measured in mmHg (millimeters of mercury). Normal blood pressure is around 120/80 mmHg, where 120 is systolic (heart contracting) and 80 is diastolic (heart relaxing) pressure.
Why do deep-sea divers need to worry about pressure?
Water pressure increases by 1 atmosphere (14.7 psi) every 10 meters of depth. At 30 meters, divers experience 4 atmospheres of pressure, affecting gas absorption and requiring careful decompression.