Convert Atmospheres to Pascals
1 atmosphere (atm) equals 101325 pascals (Pa).
1 atm = 101325 Pa
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk atmosphere to pascal converter to paste a column from Excel.
How to Convert Atmosphere to Pascal
- 1 atm = 101325 Pa
- 1 Pa = 0.000009869232667 atm
- Example: convert 15 atm to Pa: 15 atm = 15 × 101325 Pa = 1519875 Pa
Formula
Pa = atm × 101325
Derivation from SI units:
- 1 atm = 101 325 Pa (exact, by definition)
- 1 Pa = 1 N/m² = 1 kg·m⁻¹·s⁻²
Both units are defined exactly, so the factor is exact. Atmosphere definition: atmosphere; Pascal definition: pascal.
Worked examples
- 1 atm is exactly 101325 Pa.
1 atm × 101325 = 101325 Pa - A diver at about 20 m depth is under roughly 3 atm absolute, which is 303975 Pa.
3 atm × 101325 = 303975 Pa
Atmosphere to Pascal conversion table
| Atmospheres (atm) | Pascals (Pa) |
|---|---|
| 0.001 atm | 101.325 Pa |
| 0.01 atm | 1013.25 Pa |
| 0.1 atm | 10132.5 Pa |
| 0.25 atm | 25331.25 Pa |
| 0.5 atm | 50662.5 Pa |
| 1 atm | 101325 Pa |
| 1.5 atm | 151987.5 Pa |
| 2 atm | 202650 Pa |
| 2.5 atm | 253312.5 Pa |
| 3 atm | 303975 Pa |
| 4 atm | 405300 Pa |
| 5 atm | 506625 Pa |
| 10 atm | 1013250 Pa |
| 20 atm | 2026500 Pa |
| 50 atm | 5066250 Pa |
| 100 atm | 10132500 Pa |
| 200 atm | 20265000 Pa |
| 300 atm | 30397500 Pa |
| 1000 atm | 101325000 Pa |
Where it's used
Textbook gas-law and thermodynamics problems give pressures in atmospheres. Converting to pascals puts them in the coherent SI unit needed for PV = nRT with R = 8.314 J/(mol·K).
Atmosphere to other pressure units
| Conversion | 1 atm equals |
|---|---|
| atmosphere to pascal | 101325 Pa |
| atmosphere to kilopascal | 101.325 kPa |
| atmosphere to megapascal | 0.101325 MPa |
| atmosphere to psi | 14.69594878 psi |
| atmosphere to bar | 1.01325 bar |
| atmosphere to millibar | 1013.25 mbar |
| atmosphere to decibar | 10.1325 dbar |
| atmosphere to torr | 760 Torr |
| atmosphere to millimeter of mercury | 759.9998917 mmHg |
| atmosphere to millimeter of water | 10332.27453 mmH₂O |
| atmosphere to centimeter of water | 1033.227453 cmH₂O |
| atmosphere to inch of water | 406.7824617 inH₂O |
| atmosphere to inch of water (60 °F) | 407.1893586 inH₂O (60 °F) |
| atmosphere to inch of mercury | 29.92125558 inHg |
| atmosphere to barye | 1013250 Ba |
Frequently asked questions
Why use 101325 Pa for atmospheric pressure?
It is the defined standard atmosphere, adopted in 1954 and close to mean sea-level pressure. Real weather pressure varies by a few percent around it.
How many pascals are in 1 atmosphere?
1 atm = 101325 Pa.
How do I convert atmospheres to pascals?
Multiply the value in atm by 101325. For example, 15 atm × 101325 = 1519875 Pa.
Is the atm to Pa conversion exact?
Yes. Both units are defined exactly, and 1 atm is exactly 101325 Pa.
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "atmosphere, standard (atm)".
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 4, coherent derived units with special names.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Atmospheres to Pascals. Retrieved October 17, 2026, from https://scientificconverters.com/pressure/atmosphere-to-pascal/
IEEE
Scientific Converters, "Convert Atmospheres to Pascals," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/pressure/atmosphere-to-pascal/