The calculation, without hidden assumptions
Pressure units cross several industries at once: pascals and megapascals in engineering, bar and psi in equipment and tires, hPa in weather, atm and Torr in science and vacuum work, and mmHg in medical or laboratory contexts. MAXScanner converts every supported unit through pascals with no intermediate rounding, shows the selected pair plus all equivalents, and keeps gauge-versus-absolute pressure separate from unit conversion. That distinction matters: changing psi to bar does not tell you whether the original reading was psig or psia.
How to use this calculator
Enter the pressure value and select the unit printed on the gauge, datasheet or calculation.
Choose the target unit, then use Swap when you want the inverse direction; adjust precision or scientific notation for very small or large values.
Use the all-unit panel to cross-check the same physical pressure, and handle gauge-to-absolute conversion separately using the applicable ambient pressure.
Where people use it
- •Hydraulic, pneumatic and process pressure specifications
- •Tire, compressor and equipment pressure comparisons
- •Weather, vacuum and laboratory unit conversion
- •Reading imported drawings and datasheets that mix psi, bar, kPa and MPa
Example: 1 bar to psi
One bar is exactly 100,000 Pa. Dividing by the pascal value of one pound-force per square inch gives about 14.5037738 psi. The same input can also be read immediately in kPa, MPa, atm and Torr.
What the result does not assume
- •Gauge and absolute pressure use different zero references. This page converts units only and does not add or subtract atmospheric pressure automatically.
- •Torr and conventional mmHg are extremely close but are kept as distinct definitions. inHg is explicitly treated as the conventional 0 °C mercury-column unit.
Frequently asked questions
How many psi are in one bar?+
One bar is about 14.5037738 psi because bar is exactly 100,000 Pa and psi is derived from the exact pound-force and inch definitions.
Is 1 atm the same as 1 bar?+
No. One standard atmosphere is exactly 101,325 Pa, while one bar is exactly 100,000 Pa.
Can this convert psig to psia?+
Not from the unit labels alone. Gauge-to-absolute conversion also requires the ambient reference pressure; use this page only to change pressure units.
Are Torr and mmHg exactly identical?+
They are extremely close in ordinary work, but Torr is exactly 1/760 of a standard atmosphere while conventional mmHg is maintained as a separate factor here.
Semantic next steps
Continue the calculation
These links move to a different input, formula or project stage rather than a keyword variation of this page.
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Keep the result connected to the real job
MAXScanner keeps the formula and assumptions beside the result so you can verify the number before using it in a drawing, estimate, specification, worksheet or document. Where a supplier, manufacturer, drawing or applicable standard owns a requirement, that source remains authoritative.