Kilopascals to Standard Atmospheres (kPa to atm)

1 kilopascal equals 0.009869232667 standard atmospheres (rounded).

1 kilopascal = 0.009869232667 standard atmospheres

How to convert kilopascals to standard atmospheres

To convert kilopascals to standard atmospheres, multiply the number of kilopascals by 0.009869232667. The factor is rounded to 10 significant digits. To go the other way, multiply standard atmospheres by 101.325.

standard atmospheres = kilopascals × 0.009869232667

Example: 10 kilopascals = 0.09869232667 standard atmospheres.

About these units

Kilopascal (kPa)

Metric (SI)Current unit

1,000 pascals. Used for tire pressures, weather reports in many countries and engineering.

Kilopascal is the form of the pascal that most people actually use. The pascal itself is very small, so outside meteorology the kilopascal became the common choice in most fields, and it equals one centibar. Medical elastography reports tissue stiffness in kPa, and Canada reports atmospheric pressure in kPa rather than hectopascals.

A standard atmosphere is 101.325 kPa. In 1982 IUPAC recommended a different reference for chemistry, a standard pressure of exactly 100 kPa, which split the older convention of 1 atm into two competing standards.

Blood pressure shows how the units line up. One mmHg is 0.13332 kPa, and a normal reading is below about 16.0 kPa systolic and 10.7 kPa diastolic, the same thing as the familiar 120 over 80 in millimeters of mercury.

1 kilopascal = 1,000 pascals (exactly).

Sources: Wikipedia: Pascal (unit); Wikipedia: Standard atmosphere (unit); Wikipedia: Millimetre of mercury

Standard Atmosphere (atm)

Metric (SI)Current unit

Exactly 101,325 pascals, the average pressure of the atmosphere at sea level.

A column of mercury about 76 cm tall was Torricelli's measure of the air, and the standard atmosphere began as exactly that: the pressure of 760 mm of mercury at 0 degrees Celsius under standard gravity. It was used as a reference for physical and chemical properties, and the Celsius scale set 100 degrees as the boiling point of water at that pressure.

In 1954 the 10th CGPM confirmed the standard atmosphere as exactly 1,013,250 dynes per square centimeter, which is 101,325 pascals, a definition that no longer depends on the properties of any substance.

In practice one atmosphere is about 1.01325 bar, 760 mmHg, 14.696 psi or 29.92 inHg, and roughly the pressure of 10.33 meters of water. Chemistry splits on it: until 1982 standard temperature and pressure used 1 atm, but that year IUPAC recommended a standard pressure of exactly 100 kPa instead.

1 standard atmosphere = 101,325 pascals (exactly).

Sources: Wikipedia: Standard atmosphere (unit); Wikipedia: Atmospheric pressure; Wikipedia: Evangelista Torricelli

Related conversions

See all pressure units.