kPa to PSI Converter: Kilopascals to Pounds per Square Inch

How to use the kpa to psi converter

1. Enter a pressure value in the Kilopascals (kPa) field to convert to psi, or use the PSI field to convert back to kilopascals.
2. Adjust the Decimal places field if you need more or fewer digits of precision.
3. Read the converted result immediately below the input fields.
4. Leave one field empty; filling both will show an error since the tool needs to know which direction to convert.

How the kPa to psi conversion works

The relationship between kilopascals and pounds per square inch is defined by the exact NIST SP 811 conversion factor. One pascal equals one newton per square meter, and one pound-force per square inch equals exactly 6,894.757293168361 pascals. Therefore, one kilopascal (1,000 Pa) equals exactly 0.14503773773020922 psi.

To convert kilopascals to psi, multiply by this factor:

psi = kPa x 0.14503773773020922

For example, standard atmospheric pressure is 101.325 kPa. Multiplying gives 101.325 x 0.14503773773020922 = 14.6959488... psi. To go from psi to kilopascals, divide by the same factor or multiply by 6.894757293168361.

Common pressure conversions reference

This table lists frequently used pressure values converted between kilopascals and psi. All values are rounded to four decimal places for readability.

Where kilopascals and psi are used

Kilopascals belong to the International System of Units (SI) and are the standard pressure measurement in science, engineering, and most countries worldwide. Weather reports in Canada, Australia, and Europe typically use hectopascals or kilopascals. Tire pressures on vehicles sold outside the United States are often labeled in kPa or bar. If you need to relate these to other metric units, tools like atm to kPa or pascals to psi cover adjacent conversions.

Pounds per square inch remains the dominant pressure unit in the United States for everyday applications. Scuba tanks, air compressors, hydraulic systems, and automotive tires in the US market are rated in psi. Engineers working with international specifications frequently need to perform a psi to kPa conversion to ensure components meet safety standards across regions.

Precision and floating point considerations

When converting between pressure units, the number of decimal places matters. A difference of 0.01 psi might be negligible for inflating a basketball but critical when calibrating laboratory equipment or setting relief valves on industrial boilers. This converter lets you choose up to 15 decimal places so you can match the precision your application requires.

Internally, JavaScript uses IEEE 754 double-precision floating-point arithmetic, which provides about 15 to 17 significant decimal digits. The exact NIST factor (0.14503773773020922...) has more digits than a single float can store perfectly, but the error introduced is far smaller than any physical pressure gauge can measure. For practical engineering work, six decimal places is more than sufficient.

Relationship to other pressure units

Kilopascals and psi sit within a broader system of pressure measurements. One bar equals exactly 100 kPa, making it a convenient bridge between SI and imperial contexts. You can convert between those using the psi to bar tool. Standard atmospheric pressure is defined as exactly 101.325 kPa, 14.695949 psi, or 1.01325 bar.

In vacuum science and HVAC work, pressures may be expressed in torr, millimeters of mercury, or inches of water column. Understanding how kilopascals to psi fits into this larger picture helps prevent unit mismatch errors, which have historically caused costly engineering failures. Always verify which absolute or gauge pressure reference your specification uses before converting.

Worked examples