Millibar to PSI Converter
One Millibar equals 0.01450377377 PSI (1 mbar = 0.01450377377 psi). Multiply a Millibar value by 0.01450377377 to get the equivalent in PSI. Use the calculator above for instant results, or follow the formula, worked examples, and reference table below.
Formula
psi = mbar × 0.01450377377
Multiply the Millibar value by 0.01450377377 to get the equivalent value in PSI.
Example Conversions
1 Millibar (mbar)
0.01450377377 PSI (psi)
5 Millibar (mbar)
0.07251886887 PSI (psi)
10 Millibar (mbar)
0.1450377377 PSI (psi)
25 Millibar (mbar)
0.3625943443 PSI (psi)
100 Millibar (mbar)
1.450377377 PSI (psi)
Conversion Table
| Millibar (mbar) | PSI (psi) |
|---|---|
| 0.1 | 0.001450377377 |
| 0.5 | 0.007251886887 |
| 1 | 0.01450377377 |
| 2 | 0.02900754755 |
| 5 | 0.07251886887 |
| 10 | 0.1450377377 |
| 25 | 0.3625943443 |
| 50 | 0.7251886887 |
| 100 | 1.450377377 |
| 250 | 3.625943443 |
| 500 | 7.251886887 |
| 1000 | 14.50377377 |
How to Convert Manually
Use these steps to convert Millibar values to PSI without the calculator.
- Write down the value in Millibar (mbar) that you want to convert.
- Multiply that value by 0.01450377377.
- For example, 10 Millibar × 0.01450377377 = 0.1450377377 PSI.
- Label the result as PSI (psi).
Relative Size Comparison
This chart shows the visual difference in size between exactly one Millibar and one PSI.
About Millibar and PSI
The millibar is one thousandth of a bar, identical to the hectopascal. Meteorology has used millibars for surface pressure maps and storm intensity for a century. The pound per square inch is about 6,894.757 pascals. US tire pressures, water systems, and industrial equipment are rated in psi. One Millibar equals 0.01450377377 PSI (1 mbar = 0.01450377377 psi). Millibar to PSI conversion comes up most often in weather maps and forecasts and in hurricane intensity reporting, typically when figures need restating for US tire pressure.
Precision and Rounding: Several pressure factors are exact by definition (1 atm = 101,325 Pa; 1 bar = 100,000 Pa) while others, like psi and mmHg, are derived and carry long decimals. Tire and weather readings tolerate whole-number rounding; calibration, medicine, and process engineering need the full factor before rounding.
Conversion factors per NIST Special Publication 811 and the BIPM SI Brochure (9th edition) (reference).
Worked Example
15 Millibar equals 0.2175566066 PSI.
15 mbar × 0.01450377377 = 0.2175566066 psi
FAQ
How do I convert Millibar to PSI?
Multiply the Millibar value by 0.01450377377 to get the equivalent value in PSI.
What is the formula for Millibar to PSI?
The formula is psi = mbar × 0.01450377377.
How many PSI are in 1 Millibar?
1 Millibar equals 0.01450377377 PSI.
Can I convert PSI back to Millibar?
Yes. 1 PSI equals 68.94757293 Millibar, and the related converter can reverse the calculation.
What are common names for Millibar and PSI?
Millibar is shown as mbar and may also be searched as millibars, mb. PSI is shown as psi and may also be searched as pounds per square inch, lbf/in².
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