ATM Pressure Converter
Convert atmospheres (atm) to and from Pascals, kPa, bar, psi, mmHg, Torr, and inHg. Bidirectional conversion with preset values, reference table, and quick formulas.
kPa to ATM Converter
Convert between kilopascals and atmospheres with bidirectional conversion, Pa/bar/psi equivalents, and reference table.
kPa
Atmospheres (atm)⧉
0.01 atm
Converted from kPa
Pascals (Pa)⧉
1,000.00 Pa
Converted from kPa
Bar⧉
0.01 bar
Converted from kPa
PSI⧉
0.15 psi
Converted from kPa
mmHg⧉
7.50 mmHg
Converted from kPa
Conversion Table
| kPa | atm | Pa | bar | psi | mmHg |
|---|---|---|---|---|---|
| 0.01 | 0.00 | 10.00 | 0.00 | 0.00 | 0.08 |
| 0.10 | 0.00 | 100.00 | 0.00 | 0.01 | 0.75 |
| 0.50 | 0.00 | 500.00 | 0.01 | 0.07 | 3.75 |
| 1.00 | 0.01 | 1,000.00 | 0.01 | 0.15 | 7.50 |
| 2.00 | 0.02 | 2,000.00 | 0.02 | 0.29 | 15.00 |
| 5.00 | 0.05 | 5,000.00 | 0.05 | 0.73 | 37.50 |
| 10.00 | 0.10 | 10,000.00 | 0.10 | 1.45 | 75.01 |
| 50.00 | 0.49 | 50,000.00 | 0.50 | 7.25 | 375.03 |
| 100.00 | 0.99 | 100,000.00 | 1.00 | 14.50 | 750.06 |
| 1,000.00 | 9.87 | 1,000,000.00 | 10.00 | 145.04 | 7,500.64 |
Quick Formulas
kPa → atm⧉
atm = kPa ÷ 101.325
Divide by 101.325
atm → kPa⧉
kPa = atm × 101.325
Multiply by 101.325
kPa → psi⧉
psi = kPa × 0.14504
Multiply by 0.14504
kPa → bar⧉
bar = kPa ÷ 100
Divide by 100
atm → psi⧉
psi = atm × 14.696
Multiply by 14.696
atm → bar⧉
bar = atm × 1.01325
Multiply by 1.01325
Planning notes, formulas, and examples
About the kPa to ATM Converter
Kilopascals and atmospheres are both common pressure units, but they signal different contexts. kPa is the practical SI-style unit used in engineering, weather, and equipment specs, while atm is the classic chemistry and gas-law reference pressure. They are close enough to be easy to compare, yet different enough that the conversion factor matters when you are solving a gas law, reading a weather map, or checking an equipment specification.
This converter handles both directions and also shows Pa, bar, psi, and mmHg. That makes it useful when a reading in kPa has to be compared with a chemistry value in atm, or when an atmosphere-based reference needs to be translated into a more engineering-friendly number. It also helps when a lab report, a diving table, or a reference chart uses atm but the rest of your workflow is written in metric pressure units.
Use it when you need to move between metric pressure reporting and atmosphere-based scientific reference points without memorizing the 101.325 factor. The reference table gives you quick checks for common pressures instead of making you recalculate the same ratio over and over.
When This Page Helps
kPa and atm describe the same pressure in two communities that often talk past each other. This page keeps both views visible and makes it easier to compare engineering values with chemistry, weather, and diving references, which is useful whenever a calculation crosses from one convention into the other. It is also a practical guardrail against rounding a result too early and losing the precision you need for a gas-law or reference-pressure check.
How to Use the Inputs
- Select the input unit from the dropdown menu.
- Enter your pressure value in the input field.
- View all converted values in the output cards below.
- Use the preset buttons for common values.
- Review the conversion table for a range of values.
- Expand the reference section to see real-world pressure examples.
- Check the quick formulas for the mathematical relationships.
Formula used
kPa to atm: atm = kPa ÷ 101.325
atm to kPa: kPa = atm × 101.325
kPa to psi: psi = kPa × 0.145038
kPa to bar: bar = kPa ÷ 100Example Calculation
Result: 1.974 atm
200 kPa ÷ 101.325 = 1.974 atm. This is roughly twice atmospheric pressure, similar to the pressure at 10 meters under water.
Tips & Best Practices
- 1 atm = 101.325 kPa is the fundamental conversion factor to memorize.
- For a quick estimate: kPa ÷ 100 ≈ atm (within 1.3%).
- Standard atmosphere was redefined: 1 atm = 101,325 Pa exactly.
- Weather maps in kPa: normal range is about 97-104 kPa.
- IUPAC standard pressure is 100 kPa (1 bar), not 101.325 kPa (1 atm).
- In gas law problems (PV=nRT), use kPa with R = 8.314 L·kPa/(mol·K).
kPa and atm in Science
The mole concept in chemistry traditionally uses STP at 0°C and 1 atm (101.325 kPa), giving a molar volume of 22.414 L/mol for ideal gases. The newer IUPAC standard uses 0°C and 100 kPa (1 bar), giving 22.711 L/mol.
When to Use Each Unit
Use atm when solving gas law problems in general chemistry courses (unless instructed otherwise). Use kPa in engineering calculations, when working with SI units, or when using R = 8.314. International standards increasingly prefer kPa or bar over atm.
Pressure in Different Fields
Medical: mmHg (blood pressure). Chemistry: atm or bar. Engineering: kPa, MPa, or psi. Meteorology: hPa, kPa, or mbar. Diving: atm or bar. This converter helps bridge all these unit systems.
Sources & Methodology
Last updated:
Frequently Asked Questions
1 atm = 101.325 kPa exactly. This is the defined standard atmospheric pressure, so the conversion does not vary from one source to another.
Divide the kPa value by 101.325. For example, 150 kPa ÷ 101.325 = 1.481 atm, which is the same relationship this page uses in the opposite direction as well.
No, but they are close. 100 kPa = 1 bar = 0.9869 atm, while 1 atm = 101.325 kPa, so the difference is about 1.3%.
Use R = 8.314 L·kPa/(mol·K) when pressure is in kPa and volume in liters. With atm, use R = 0.08206 L·atm/(mol·K), so the gas-law units stay consistent.
Canada and some other countries use kPa for weather because it is an SI unit. Normal weather pressure ranges from about 97 to 104 kPa, which is why the unit works well for daily forecasts and synoptic maps.
1 kPa = 10 hPa (hectopascals). Meteorologists often use hPa, which is the same numerical scale as millibars, so standard pressure becomes 1013.25 hPa = 101.325 kPa.
More in this topic
ATM to Pascals Converter
Convert between atmospheres (atm) and Pascals (Pa). Bidirectional converter with kPa, hPa, mbar, and bar outputs, reference table, and preset values.
Bar to ATM Converter
Convert between bar and atmospheres (atm) with bidirectional conversion, PSI/kPa/mmHg equivalents, reference table, and preset values.