A standard atmosphere is exactly 101,325 pascals.
Atmospheres to Pascals Converter — atm to Pa
Convert Atmosphere (atm) to Pascal (Pa) using the exact conversion factor (1 atmosphere = 101,325 pascal). See the formula, worked examples, conversion table, unit comparison, history, and common uses.
Atmospheres to Pascals converter
Converter
Engineering Converter
Convert common stress, force, torque, power, and energy units used in engineering.
Context values
Some unit families need one extra value for a physically accurate result.
The pascal is one newton per square meter.
Result = input x 101325 / 1.
Stress Pressure units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Atmospheres to Pascals
Atmosphere and Pascal both measure a quantity used in structural or mechanical engineering — commonly stress, pressure, force, torque, power, or energy — where converting between the unit conventions used in different regions, industries, or equipment specifications is a routine part of design work. Atmosphere is typically associated with widely used internationally in chemistry, meteorology, and diving/aviation contexts alongside the pascal and bar, while Pascal is typically associated with standard scientific pressure unit worldwide.
Formula
pascals = atmospheres × 101325
This factor comes from each unit's defined relationship to the category's base unit: 1 atmosphere equals 101325 base units, and 1 pascal equals 1 base unit, so dividing one by the other gives the direct atmosphere-to-pascal factor of 101325.
Simple example
1 atm × 101325 = 101,325 Pa
1 atmosphere = 101,325 pascals.
Real-world example
100 atm × 101325 = 10,132,500 Pa
100 atmospheres = 10,132,500 pascals.
Conversion table
| Atmosphere (atm) | Pascal (Pa) |
|---|---|
| 1 atm | 101,325 Pa |
| 10 atm | 1,013,250 Pa |
| 50 atm | 5,066,250 Pa |
| 100 atm | 10,132,500 Pa |
| 500 atm | 50,662,500 Pa |
| 1,000 atm | 101,325,000 Pa |
Reverse conversion: Pascal to Atmosphere
1 Pa × 0.000009869232667 = 0.0000098692 atm
1 pascal = 0.0000098692 atmospheres.
atmospheres = pascals × 0.00000986923266716
For a page dedicated to this direction, see Pascal to Atmosphere.
Atmosphere vs. Pascal
| Aspect | Atmosphere | Pascal |
|---|---|---|
| Family | non-SI unit accepted for use with the SI | SI derived unit |
| Typical use | Chemistry (standard conditions are often defined at 1 atm) | Scientific and engineering pressure measurement worldwide |
| Where it's used | Widely used internationally in chemistry, meteorology, and diving/aviation contexts alongside the pascal and bar | Standard scientific pressure unit worldwide |
Understanding the Atmosphere
Atmosphere (atm) measures pressure. Defined as exactly 101,325 pascals, originally based on the average atmospheric pressure at mean sea level. It is classified as a non-SI unit accepted for use with the SI.
Where it's used: Widely used internationally in chemistry, meteorology, and diving/aviation contexts alongside the pascal and bar
Uses of the Atmosphere today
- Chemistry (standard conditions are often defined at 1 atm)
- Diving and aviation pressure references
- General reference for everyday atmospheric pressure
Understanding the Pascal
Pascal (Pa) measures pressure. The pascal is the SI derived unit of pressure: one newton of force per square meter. It is classified as a SI derived unit.
Where it's used: Standard scientific pressure unit worldwide
Uses of the Pascal today
- Scientific and engineering pressure measurement worldwide
- Meteorology (often as hectopascals, equivalent to millibars)
- Material science (stress and strength, typically in megapascals)
History of the Pascal
The pascal is named after Blaise Pascal, whose 17th-century experiments clarified the physics of fluid pressure and vacuum. It was adopted as the SI derived unit of pressure in 1971, replacing the older, non-coherent CGS pressure units used in much scientific work up to that point.
Historical origin. Pascal was not the invention of a single named person; it developed through the process described above.
Atmosphere — sources
- BIPM SI Brochure — Standard atmosphere listed among non-SI units with a fixed exact value in pascals.
Pascal — sources
- BIPM SI Brochure — Coherent derived units — Defines the pascal as the SI unit of pressure.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many pascals are in 1 atmosphere?
1 atmosphere equals 101,325 pascals, using the exact defined conversion factor rather than an estimate.
How do I convert atmosphere to pascal?
Multiply the atmosphere value by 101325. The converter above does this instantly to whatever precision you set.
How do I convert pascal back to atmosphere?
Use the reverse factor: 1 pascal equals 0.0000098692 atmospheres. You can also use the swap control in the converter above to flip the direction instantly.
What is a atmosphere?
Atmosphere (atm) measures pressure. Defined as exactly 101,325 pascals, originally based on the average atmospheric pressure at mean sea level. It is classified as a non-SI unit accepted for use with the SI.
What is a pascal?
Pascal (Pa) measures pressure. The pascal is the SI derived unit of pressure: one newton of force per square meter. It is classified as a SI derived unit.
Is the atmosphere to pascal conversion exact?
Yes. Defined as exactly 101,325 pascals, originally based on the average atmospheric pressure at mean sea level. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
Where is the atmosphere still used today?
Widely used internationally in chemistry, meteorology, and diving/aviation contexts alongside the pascal and bar
Why do engineering unit conventions vary so much by region and industry?
Pressure, force, and stress can be expressed in metric (pascal, newton), US customary (psi, pound-force), or older and industry-specific units (atmosphere, torr, kip) depending on the country, industry, and even the equipment manufacturer, which is why engineers routinely need to convert between them when working across specs from different sources.