Multiply by 0.0689476: psi × 0.0689476 = bar. Example: 35 psi = 2.413 bar. Reverse (bar to psi): multiply by 14.5038. Example: 2.5 bar = 36.26 psi. The factor comes from the exact definition: 1 psi = 1 lbf/in² = 6,894.76 Pa, and 1 bar = 100,000 Pa, so 1 psi = 6894.76 / 100000 bar = 0.068948 bar.

1 bar = 14.5038 psi and 1 bar = 100 kPa exactly. The bar was defined as exactly 100,000 Pa, making the bar-to-kPa conversion trivially simple (no calculation needed — just shift the decimal). Bar to psi: 1 bar = 14.504 psi; 2 bar = 29.008 psi; 2.5 bar = 36.26 psi; 3 bar = 43.51 psi. Tyre specifications often appear in all three — 2.4 bar = 240 kPa = 34.8 psi.

Multiply by 0.145038: kPa × 0.145038 = psi. Example: 220 kPa = 31.9 psi; 240 kPa = 34.8 psi; 250 kPa = 36.3 psi. Common vehicle door placards in Australia, Europe, and Japan show kPa; US vehicles show psi. The recommended inflation figures are identical pressures — just different units. At 200 kPa (29 psi), most passenger cars are noticeably under-inflated.

mmHg to kPa: mmHg × 0.133322 = kPa. Example: 120 mmHg = 16.0 kPa; 80 mmHg = 10.67 kPa. To Pa: mmHg × 133.322 = Pa. The unit mmHg (millimetre of mercury) is defined as the pressure exerted by a 1 mm column of mercury under standard gravity, which equals 133.322 Pa exactly. Blood pressure is reported in mmHg worldwide because the mercury sphygmomanometer was the first reliable measurement instrument — and clinical training is anchored to those reference values.

psi to kPa: psi × 6.89476 = kPa. Example: 30 psi = 206.84 kPa. kPa to psi: kPa × 0.145038 = psi. Example: 100 kPa = 14.504 psi. Note: 1 atm = 101.325 kPa = 14.696 psi, which means atmospheric pressure is approximately 100 kPa or 14.7 psi — useful as a quick mental anchor when cross-checking gauge vs absolute pressure values.

inHg to mbar/hPa: inHg × 33.8639 = mbar. Example: 29.92 inHg = 1013.25 mbar (standard sea-level pressure). Reverse: mbar × 0.02953 = inHg. Example: 1013 mbar = 29.91 inHg. Aviation QNH settings are given in inHg in the US and Canada, and in hPa/mbar in most other countries. Controllers and pilots crossing airspace boundaries convert between these dozens of times per flight day.

All five measure the same physical quantity — force per unit area — but use different reference scales. Pascal (Pa) is the SI unit: 1 N/m². kPa is 1,000 Pa; common in medicine and tyre specs. bar is 100,000 Pa — close to, but not equal to, 1 atmosphere. psi (pounds per square inch) is the US customary unit; 1 psi = 6,894.76 Pa. atm (atmosphere) = 101,325 Pa exactly — the mean sea-level air pressure. mmHg (millimetre of mercury) = 133.322 Pa — used in medicine. All convert via fixed multiplication factors — no offsets like temperature scales.

Torr to Pa: Torr × 133.322 = Pa. Torr to atm: Torr ÷ 760 = atm (since 1 atm = 760 Torr exactly). 1 Torr = 1 mmHg to six significant figures — they are treated as identical in most laboratory and clinical contexts. Example: 500 Torr = 500 mmHg = 66,661 Pa = 0.6579 atm. Torr appears in vacuum pump ratings, gas chromatography, and mass spectrometry — contexts where sub-atmospheric pressures matter and mmHg and Torr are used interchangeably.

Three steps: (1) Type any pressure value — decimals supported (e.g., 35 psi, 2.5 bar, 101.325 kPa, 29.92 inHg). (2) Select the source unit from the dropdown: Pa, kPa, MPa, bar, mbar, psi, atm, mmHg, Torr, inHg, kgf/cm², or inH₂O. (3) All other units update instantly. Tap Copy next to any result to place it in your clipboard. Completely free at untangletools.com/unit/category/pressure — no login during conversion.

Yes — decimal inputs are fully supported. Examples: 2.5 bar → 36.26 psi → 250 kPa; 35.5 psi → 2.448 bar → 244.8 kPa; 101.325 kPa → 1 atm → 760 mmHg. The tool uses 64-bit floating-point precision throughout, so results like 1 atm = 760.000 Torr are reproduced exactly. Precision matters in lab settings, compressed-gas work, and calibration tasks where rounding introduces cumulative error.

Yes — the full unit list is: Pa, kPa, MPa, bar, mbar (hPa), psi, atm, mmHg, Torr, inHg, kgf/cm², and inH₂O. Each is selectable as source input and all others output simultaneously with one-click copy. This covers automotive (psi, kPa, bar), medical (mmHg), meteorological (mbar, inHg), laboratory (Torr, atm, Pa), hydraulic (MPa, kgf/cm²), and HVAC (inH₂O) use cases in a single tool.

Yes. All factors use exact or internationally standardised values: 1 atm = 101,325 Pa (exact); 1 bar = 100,000 Pa (exact); 1 psi = 6,894.757293168 Pa (exact, from US survey foot); 1 inHg = 3,386.389 Pa (NIST); 1 mmHg = 133.322 Pa (BIPM). Results use full 64-bit floating-point with no intermediate rounding. Entirely free at untangletools.com/unit/category/pressure — no account required.

Absolute pressure is measured from perfect vacuum (0 Pa). Gauge pressure is measured relative to the local atmosphere — so a tyre gauge reading of 35 psi means 35 psi above atmospheric pressure, or about 49.7 psia absolute. The suffix "g" means gauge (psig, barg) and "a" means absolute (psia, bara). Gas law calculations (PV = nRT) always require absolute pressure — using gauge readings here gives incorrect results. Blood pressure, tyre pressure, and most industrial instruments report gauge pressure.

Inches of water column to psi: inH₂O × 0.036127 = psi. Example: 10 inH₂O = 0.361 psi. inH₂O to Pa: inH₂O × 249.089 = Pa. Water column units are used in HVAC (duct static pressure), residential gas supply, and low-pressure differential measurement where Pascal values would be very small. A typical home furnace duct runs at 0.5–1.0 inH₂O (124–249 Pa = 0.018–0.036 psi) — a level where psi values are too small to be practical on analogue gauges.

kgf/cm² to psi: kgf/cm² × 14.2233 = psi. Example: 100 kgf/cm² = 1,422 psi. kgf/cm² to bar: kgf/cm² × 0.980665 = bar. Example: 100 kgf/cm² = 98.07 bar. The kgf/cm² (also called "technical atmosphere" or "at") appears extensively in Japanese and older European industrial specifications — machining centres, injection moulding presses, and hydraulic presses. It is numerically close to bar (≈ 0.981 bar per kgf/cm²) but not equal, so direct substitution causes about 2 % error.

Mercury manometers were the first instruments reliable enough for clinical blood pressure measurement, introduced by Riva-Rocci in 1896. The medical profession built its training, diagnostic criteria, drug dosing thresholds (e.g., "treat if systolic > 140 mmHg"), and device design around this unit over more than a century. Despite mmHg being a non-SI unit, the WHO and medical societies worldwide retain mmHg to preserve continuity with decades of clinical research. SI-equivalent values (120 mmHg ≈ 16 kPa) are technically accurate but clinically unfamiliar — introducing kPa in clinical practice would create dangerous ambiguity in drug and alarm thresholds.

Surface weather maps use isobars — contour lines of equal pressure. European and international maps label these in hPa (hectopascals) where 1 hPa = 1 mbar = 100 Pa. US maps traditionally use both hPa and inHg. Standard sea-level pressure is 1013.25 hPa = 29.92 inHg = 1013.25 mbar. Low-pressure systems (storms) sit below 980 hPa; highs reach 1030+ hPa. A pressure fall of 20+ hPa in 24 hours signals an explosive cyclogenesis (weather bomb) — one reason meteorologists track pressure changes in fixed units like hPa rather than converting to psi or bar.

In diving, pressure increases by 1 atm (101.325 kPa = 14.696 psi) per 10 m of seawater depth. At 30 m depth, total absolute pressure = 4 atm = 405 kPa = 58.8 psi (3 atm water + 1 atm surface). A standard scuba cylinder holds air at 200–300 bar (2,900–4,350 psi). Decompression tables use metres and bar in metric countries, feet and psi in the US. A half-full tank at 100 bar = 1,450 psi = 10,000 kPa. The converter handles all of these simultaneously — useful when comparing tank specs from different manufacturers.

Oil and gas uses psi almost universally in the US and internationally for wellhead, pipeline, and reservoir pressures — primarily because US companies dominated early petroleum engineering. Pressures range from a few hundred psi (pipeline distribution) to 10,000–20,000 psi in deepwater wellheads and high-pressure hydraulic fracturing. MPa and bar appear in international standards and European equipment specs. Specific terms: SITP (shut-in tubing pressure), BHP (bottomhole pressure), and MAOP (maximum allowable operating pressure) are all reported in psi in most field documentation.

Standard steam sterilisation (autoclave) runs at 15 psig (1.034 bar gauge / 2.034 bar absolute) and 121 °C. Some cycles use 30 psig (2.07 bar gauge) for faster throughput at 134 °C. Converting: 15 psig = 103.4 kPa gauge = 204.7 kPa absolute (add 101.325 kPa for atmospheric). The gauge/absolute distinction is critical — an autoclave rated "15 psi" means gauge (psig), not absolute. Confusing the two in pharmaceutical validation documentation is a compliance failure. The converter outputs both gauge and absolute if you specify which input you have.