inch of mercury to pound/sq inch Converter
Convert inHg to psi and back with a live reference table.
1 inHg = 0.491154 psi\n5 inHg = 2.45577 psi\n10 inHg = 4.91154 psi\n25 inHg = 12.2789 psi\n50 inHg = 24.5577 psi\n100 inHg = 49.1154 psi
Why this conversion matters
Inches of mercury appear in weather and vacuum readings, while psi is easier for many equipment calculations. The widget keeps the direction explicit so you can enter either side of the pair without doing the reciprocal by hand. It is built for quick checks where a calculator, specification sheet, recipe, map, or lab note uses the other unit.
For the default example, 29.92 inHg converts to 14.6953 psi. Switching the direction shows the inverse relationship, so 14.6953 psi converts back to 29.92 inHg with the same factor.
Formula and privacy note
The calculation uses 1 inHg = 0.491154 psi. Forward conversion multiplies by that factor, and reverse conversion divides by it. Results are rounded to six significant figures for readable estimates, so very small scientific units and large planning units stay scannable. Check the unit labels before copying a result, especially when similar abbreviations appear in the same project. The reference table is generated from the same constant, and everything runs locally in your browser.
Frequently Asked Questions
What factor does this converter use?
It uses the standard factor 1 inHg = 0.491154 psi, then applies the reciprocal for the reverse direction.
Why are results rounded?
The main result is rounded to six significant figures so very large and very small values stay readable while preserving the useful precision for quick checks.
Can I convert both directions?
Yes. Choose inHg to psi or psi to inHg from the direction menu and the output updates immediately.
Is this converter private?
Yes. The conversion runs entirely in your browser, and the value you enter is not uploaded or stored.
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