bar to kPa: 1 bar = 100 kPa (exact)

The formula

kPa = bar × 100

Where the factor comes from — each unit by its definition, then its size in SI:

1 bar = 100 × kPa = 100,000 Pa
1 kPa = 1000 × Pa = 1,000 Pa

Dividing the two SI sizes gives the factor: 100, exact — every step above is a definition, not a measurement. The reverse factor is 0.01.

Pressure is force per area; the pascal is one newton per square metre. Tyres are quoted in psi or bar, weather in hPa, blood pressure in mmHg and gas laws in pascals or atmospheres.

Worked examples

A car tyre (US gauge) (32 psi): 2.20632 bar = 220.632 kPa — 2.20632 × 100 = 220.632
Sea-level air (1 atm): 1.01325 bar = 101.325 kPa — 1.01325 × 100 = 101.325
A car tyre (European gauge): 2.2 bar = 220 kPa — 2.2 × 100 = 220
A systolic blood-pressure reading (120 mmHg): 0.159987 bar = 15.9987 kPa — 0.159987 × 100 = 15.9987

Frequently asked questions

How many kilopascals is 1 bar?

1 bar = 100 kPa, exactly, from the unit definitions.

How do I convert kilopascals back to bar?

Divide by 100 — or multiply by 0.01: 1 kPa = 0.01 bar.

bar to kPa conversion table

Bar (bar)	Kilopascals (kPa)
1	100
2	200
3	300
4	400
5	500
6	600
7	700
8	800
9	900
10	1,000
15	1,500
20	2,000
25	2,500
30	3,000
40	4,000
50	5,000
60	6,000
70	7,000
75	7,500
80	8,000
90	9,000
100	10,000
150	15,000
200	20,000
250	25,000
500	50,000
1,000	100,000

Definitions: BIPM, The International System of Units (SI Brochure), 9th edition (2019), Tables 2, 4 and 8 — https://www.bipm.org/en/publications/si-brochure. Machine value of the factor: 100.