About pressure, energy & power converter
Pressure, energy, power and frequency each have several units, depending on the field. This converter handles the common ones.
Common units
- Pressure: pascal (Pa), bar, PSI (used for tyres) and atmosphere.
- Energy: joule, calorie, kilocalorie (food) and kilowatt-hour (electricity).
- Power: watt, kilowatt and horsepower.
- Frequency: hertz, kilohertz and megahertz.
Useful anchors
- 1 bar is about 100,000 Pa or 14.5 PSI.
- 1 kWh is 3.6 million joules and is what an electricity meter counts as one unit.
- 1 kcal is about 4184 joules.
A worked example
A car tyre needs 32 PSI. That is about 2.2 bar or 220 kPa. A food label says 2,000 kcal, which is about 8,368 kJ or 8.4 MJ. A 1 horsepower motor delivers about 746 watts.
Which units where
- Tyres and compressors use PSI or bar, while weather reports use hPa.
- Food uses kilocalories in India and kilojoules in many other countries.
- Electricity is billed in kWh, which is a unit of energy, not power.
