This converter turns atmospheres into megapascals instantly, using the exact factor 1 atmosphere = 0.101325 megapascals. Type any number and the result updates as you go — nothing is sent to a server, so the arithmetic happens entirely in your browser.
Standard atmospheric pressure by definition — 101,325 pascals exactly. Used for material strength and hydraulic systems.
Because the relationship is a simple proportion, one multiplication does the whole job. The table further down gives pre-computed values for the amounts people look up most often, and the result panel also reports the reverse conversion so you can check the figure both ways.
The formula
atmospheres- The amount you are converting, measured in atmospheres
0.101325- The exact number of megapascals in one atmosphere
megapascals- The converted result
How it works, step by step
- Enter the number of atmospheres you want to convert.
- The value is multiplied by 0.101325, the exact conversion factor.
- The result is displayed in megapascals, rounded for readability.
- The unrounded value and the reverse conversion appear underneath so you can verify it.
Worked examples
Converting 5 atmospheres
Multiply 5 by 0.101325. That gives 0.506625 megapascals. A quick sanity check: one atmosphere is smaller than one megapascal, so the number should get smaller — and it does.
Converting 72 atmospheres
72 × 0.101325 = 7.2954 megapascals. Working backwards, 7.2954 ÷ 0.101325 returns 72 atmospheres, which confirms the factor is applied the right way round.
How to read your score
Frequently asked questions
How many megapascals are in one atmosphere?
Exactly 0.101325. Every conversion on this page is that single number multiplied by your input, so the result carries no rounding error beyond what is shown.
What is the formula to convert atmospheres to megapascals?
Megapascals = atmospheres × 0.101325. To reverse it, divide instead: atmospheres = megapascals ÷ 0.101325, which is the same as multiplying by 9.869232667.
Is the atmosphere bigger than the megapascal?
No. One atmosphere is only 0.101325 of a megapascal, so the megapascal is the larger unit.
Why does my answer differ slightly from other atmospheres to megapascals converters?
Most differences come from rounding the factor too early. This tool keeps full double precision through the calculation and only rounds at the final display step, and it also shows the unrounded value so you can see exactly where any difference appears.
What is a atmosphere?
Standard atmospheric pressure by definition — 101,325 pascals exactly.
What is a megapascal?
Used for material strength and hydraulic systems.
Atmospheres to megapascals reference table
| Atmospheres | Megapascals |
|---|---|
| 0.5 atm | 0.050662 MPa |
| 1 atm | 0.101325 MPa |
| 2 atm | 0.20265 MPa |
| 3 atm | 0.303975 MPa |
| 5 atm | 0.506625 MPa |
| 10 atm | 1.0132 MPa |
| 15 atm | 1.5199 MPa |
| 20 atm | 2.0265 MPa |
| 25 atm | 2.5331 MPa |
| 50 atm | 5.0663 MPa |
| 75 atm | 7.5994 MPa |
| 100 atm | 10.1325 MPa |
| 250 atm | 25.3313 MPa |
| 500 atm | 50.6625 MPa |
| 1000 atm | 101.325 MPa |
Exact factor: 1 atmosphere = 0.101325 megapascals. Values rounded for display.