🌍 Atmosphere (atm) Conversion
Translate atmospheric pressure into kPa, hPa, psi, mmHg, inHg, and more.
Essential for weather stations, HVAC designers, and laboratory work.
1 Atmospheres (atm) equals
101.325 Kilopascals (kPa)
Other Units
Pascals (Pa)
101,325
Hectopascals (hPa)
1,013.25
Megapascals (MPa)
0.101325
Bar (bar)
1.01325
Atmospheres (atm)
1
Pounds per square inch (psi)
14.69595
Kips per square inch (ksi)
0.014696
Pounds per square inch gauge (psig)
-0
Torr (Torr)
760
Millimeters of mercury (mmHg)
759.99989
Inches of mercury (inHg)
29.9213
Inches of water column (inHâ‚‚O)
406.7825
Millibar (mbar)
1,013.25
Kilogram-force per square centimeter (kgf/cm²)
1.03323
How to Use This Calculator
Enter the pressure
Start with atmospheric pressure or any other unit supported in the dropdown.
Select target units
Switch to kilopascals, hectopascals, psi, mmHg, inHg, and more.
Review quick references
Copy multiple conversions for weather reports, vacuum specs, or calibration logs.
Formula
1 atm = 101.325 kPa = 1,013.25 hPa = 14.6959 psi = 29.9213 inHg = 760 Torr
Conversions route through pascals: Pa = atm Ă— 101,325
Target Unit = Pascals Ă· Conversion Factor
Use the formula breakdown to confirm the calculation logic or perform the conversion manually if needed.
Full Description
Atmospheric pressure appears in many disciplines—from meteorology to vacuum system design. Converting between atm, kPa, psi, and inches of mercury keeps your data aligned with audience expectations.
This calculator uses exact SI relationships so you can trust the results for calibration certificates, research papers, or HVAC load calculations.
Combine it with the barometric and bar-to-psig calculators when you need specialized contexts such as weather station outputs or gauge vs. absolute comparisons.
Frequently Asked Questions
Is atm an absolute pressure unit?
Yes. 1 atmosphere equals 101,325 Pascals. For gauge pressure, use units like psig which subtract ambient pressure.
What’s the difference between kPa and hPa?
They differ by a factor of 10 (1 kPa = 10 hPa). Meteorologists often use hPa because the numbers align with millibars.
Can I convert vacuum readings?
Yes. Vacuum gauges often report in Torr or mmHg. Use the dropdown to translate between those and atm.
Does temperature affect the conversion?
These conversions are purely unit-based. If you need temperature corrections (e.g., gas densities), handle that separately.