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Bar to kilopascals

Multiply bar by 100 to get kilopascals.

1 bar = 100 kPaNIST SP 811
bar
300kPa

3 bar = 300 kPa

How to convert bar to kilopascals

The kilopascal is one thousand pascals (10³ Pa), the metric pressure unit. The bar is exactly 100 000 pascals (100 kPa), close to one atmosphere.

Worked example — 3 bar: 3 × 100 = 300 kPa.

Bar to kilopascals table

Common conversions. The reverse table is on kilopascals to bar.
BarKilopascals
0.5 bar50 kPa
1 bar100 kPa
1.5 bar150 kPa
2 bar200 kPa
3 bar300 kPa
5 bar500 kPa
10 bar1,000 kPa
20 bar2,000 kPa
50 bar5,000 kPa

Reverse and related

About bar and kilopascals

Bar (bar)

1 bar = 100 kPa

Definition. Exactly 100 000 pascals (100 kPa), close to one atmosphere

History and origin

The bar was introduced in the early twentieth century by the meteorologist Vilhelm Bjerknes, defined as exactly 100 000 pascals, close to average sea-level air pressure. Its name comes from the Greek for weight.

Current use

The bar is common outside the United States for tyre pressure, diving and weather, where the closely related millibar is also used.

Source: NIST SP 811, App. B; ISO 80000-4. Exact SI values are definitional (bar = 10⁵ Pa, atm = 101 325 Pa) or derived from the pound (NIST HB 44) and standard gravity 9.80665 m/s² (psi)

Kilopascal (kPa)

1 kPa = 0.01 bar

Definition. One thousand pascals (10³ Pa), the metric pressure unit

History and origin

The kilopascal is one thousand pascals, a metric multiple of the SI pressure unit. It gives conveniently sized numbers for everyday pressures.

Current use

Kilopascals are used for tyre pressure in metric countries and throughout engineering.

Source: NIST SP 811, App. B; ISO 80000-4. Exact SI values are definitional (bar = 10⁵ Pa, atm = 101 325 Pa) or derived from the pound (NIST HB 44) and standard gravity 9.80665 m/s² (psi)

Where people use this

Bar: tyre pressure outside the US, diving, weather. Kilopascals: tyre pressure (metric), engineering. 1 bar is exactly 100 kPa.

How we know this is right
The factor is fixed by the standards that define the units, not chosen — so it is exact, not a measurement:
1 kPa = 0.01 bar, so 1 bar = 1 ÷ 0.01 = 100 kPa.

Every value is carried to full double precision; the display is rounded.

Both units are defined in NIST SP 811, App. B; ISO 80000-4. Exact SI values are definitional (bar = 10⁵ Pa, atm = 101 325 Pa) or derived from the pound (NIST HB 44) and standard gravity 9.80665 m/s² (psi).

Questions people ask

How many kPa in a bar?

One bar is exactly 100 kPa.

How many kPa is 2 bar?

2 bar is 200 kPa.

How many bar is 250 kPa?

250 kPa is 2.5 bar.

All bar conversions