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Atmospheres to kilopascals

Multiply atmospheres by 101.325 to get kilopascals.

1 atm = 101.325 kPaNIST SP 811
atm
303.975kPa

3 atm = 303.975 kPa

How to convert atmospheres to kilopascals

The kilopascal is one thousand pascals (10³ Pa), the metric pressure unit. The atmosphere is the standard atmosphere, exactly 101 325 pascals.

Worked example — 3 atm: 3 × 101.325 = 303.975 kPa.

Atmospheres to kilopascals table

Common conversions. The reverse table is on kilopascals to atmospheres.
AtmospheresKilopascals
0.5 atm50.6625 kPa
1 atm101.325 kPa
1.5 atm151.9875 kPa
2 atm202.65 kPa
3 atm303.975 kPa
5 atm506.625 kPa
10 atm1,013.25 kPa
50 atm5,066.25 kPa
100 atm10,132.5 kPa

Reverse and related

About atmospheres and kilopascals

Atmosphere (atm)

1 atm = 101.325 kPa

Definition. The standard atmosphere, exactly 101 325 pascals

History and origin

The standard atmosphere was defined as a reference pressure of exactly 101 325 pascals, close to average pressure at sea level. It gave a convenient benchmark before the pascal became standard.

Current use

Atmospheres are used in diving, chemistry and when describing pressure at altitude.

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 = 0.00986923 atm

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

Atmospheres: diving, chemistry, altitude. Kilopascals: tyre pressure (metric), engineering. 1 atm is exactly 101.325 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 = 0.009869232667 atm, so 1 atm = 1 ÷ 0.009869232667 = 101.325 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 an atmosphere?

One atmosphere is exactly 101.325 kPa.

How many kPa is 2 atm?

2 atm is exactly 202.65 kPa.

How many kPa is standard pressure?

Standard atmospheric pressure is 101.325 kPa.

All atmosphere conversions