Gauge ↔ Absolute Pressure Converter
Convert gauge to absolute pressure (and vacuum) at any barometric pressure.
Gas-law and NPSH math need absolute pressure; gauges read relative to today's barometer. At altitude P_atm drops ~12 kPa per 1,000 m.
Formula
Gauge ↔ Absolute Pressure Converter is a free gauge to absolute pressure for process, mechanical and water engineers — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Gauge ↔ Absolute Pressure Converter
Convert gauge to absolute pressure (and vacuum) at any barometric pressure. The calculation implements P_abs = P_gauge + P_atm (Çengel, Thermodynamics, §1-9). Gas-law and NPSH math need absolute pressure; gauges read relative to today's barometer. At altitude P_atm drops ~12 kPa per 1,000 m.
How to use Gauge ↔ Absolute Pressure Converter
- 1Enter Gauge pressure in kPa(g) (Negative = vacuum).
- 2Enter Barometric pressure in kPa.
- 3Read Absolute pressure, Absolute instantly — no submit button needed.
- 4Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Gauge ↔ Absolute Pressure Converter?
- ✓Implements the standard formula — P_abs = P_gauge + P_atm
- ✓Reference cited on-page: Çengel, Thermodynamics, §1-9
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Live worked example: the substitution recomputes from your numbers
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Gauge ↔ Absolute Pressure Converter use?+
It computes P_abs = P_gauge + P_atm, per Çengel, Thermodynamics, §1-9. The formula is displayed under the result along with a worked example substituted with your own inputs.
What should I keep in mind when using this calculator?+
Gas-law and NPSH math need absolute pressure; gauges read relative to today's barometer. At altitude P_atm drops ~12 kPa per 1,000 m.
Does this work for any fluid?+
Yes — density and viscosity are inputs (with common fluids suggested in the field hints), so the same physics applies to water, oils, gases and process fluids. Compute always runs in SI internally, so unit mix-ups can't corrupt the result.
Is the Gauge ↔ Absolute Pressure Converter free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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