Pressure Converter — PSI to Bar, kPa to PSI Calculator

Pressure measures how much force acts on each unit of area. Tires, hydraulics, HVAC systems, scuba tanks, espresso machines, and blood-pressure cuffs all quote different units — PSI in the US, bar in much of Europe, pascals and kilopascals in engineering, millimetres of mercury in medicine. This converter translates between them from a single input: choose From and To units, enter a value, and read the result instantly.

Supported units include PSI, bar, pascal (Pa), kilopascal (kPa), megapascal (MPa), atmosphere (atm), millibar (mbar), millimetres of mercury (mmHg), and torr. Calculations use NIST-standard factors and run entirely in your browser — nothing is uploaded.

The most common cross-border conversion is between pound-force per square inch (PSI) and bar. US automotive tires, compressors, and industrial gauges use PSI; European datasheets and diving tables often use bar. The relationship is fixed — not an approximation.

bar = psi ÷ 14.503773773  ·  psi = bar × 14.503773773

Quick anchors: 1 psi ≈ 0.0689 bar · 2 psi ≈ 0.138 bar · 10 psi ≈ 0.689 bar · 30 psi ≈ 2.07 bar · 70 psi ≈ 4.83 bar · 90 psi ≈ 6.21 bar · 100 psi ≈ 6.895 bar · 140 psi ≈ 9.65 bar. Car tyre pressure around 32–35 psi equals roughly 2.2–2.4 bar. Espresso machines often run near 9 bar (about 130 psi).

To go from bar to PSI, multiply bar by 14.5038. European tyre labels, compressor ratings, and hydraulic schematics frequently show bar; US shops and gauges read PSI.

• 1 bar = 14.504 psi
• 2 bar ≈ 29.0 psi
• 2.5 bar ≈ 36.3 psi
• 4 bar ≈ 58.0 psi
• 5 bar ≈ 72.5 psi
• 10 bar ≈ 145.0 psi
• 12 bar ≈ 174.0 psi
• 15 bar ≈ 217.6 psi
• 20 bar ≈ 290.1 psi
• 200 bar ≈ 2,901 psi

A 2 bar tyre pressure target is a useful mental shortcut when comparing with US 29 psi ratings.

SI pressure uses the pascal (Pa). Kilopascals and megapascals appear on engineering drawings, material specs, and tyre labels in countries that use kPa instead of PSI or bar.

1 bar = 100 kPa = 100,000 Pa · 1 MPa = 10 bar · 1 kPa = 0.145038 psi

Divide kPa by 100 to get bar; multiply bar by 100 for kPa. For PSI: multiply kPa by 0.145038, or divide PSI by 6.89476 to get kPa. Examples: 100 kPa ≈ 14.5 psi (common passenger tyre rating) · 200 kPa ≈ 29 psi · 300 kPa ≈ 43.5 psi · 350 kPa ≈ 50.8 psi.

Megapascals scale for high-strength materials: 1 MPa = 10 bar = 145 psi. To convert MPa to PSI, multiply by 145.038; to convert PSI to MPa, divide by 145.038. One PSI equals 6,894.76 pascals exactly.

One bar equals 1,000 millibar (mbar). In meteorology, mbar is equivalent to hectopascal (hPa). Blood pressure and vacuum gauges often quote millimetres of mercury (mmHg): 1 bar ≈ 750.06 mmHg, and 760 mmHg approximates one standard atmosphere at sea level.

To convert kPa to mmHg, multiply kPa by 7.50062. Water-column units (cmH₂O) appear in HVAC and medical contexts; although not in the dropdown, 1 cmH₂O ≈ 0.735 mmHg ≈ 0.00098 bar — convert through kPa or bar as an intermediate step for close estimates.

When comparing US gauge readings in PSI with metric equipment datasheets in kPa, multiply PSI by 6.89476.

Some Asian and European specs quote pressure in kilogram-force per square centimetre (kgf/cm²) — sometimes written kg/cm². This is a pressure unit, not mass: 1 kgf/cm² ≈ 98.07 kPa ≈ 0.9807 bar ≈ 14.22 psi. Searches that mix "kilogram" with PSI usually mean kgf/cm² pressure, not converting kilogram mass to PSI.

Gauge and absolute pressure use different zero references. PSIG and barg measure above atmospheric pressure; PSIA and bara include the ambient offset (~14.7 psi or ~1 bar at sea level). This converter handles unit magnitudes — add or subtract one atmosphere when switching between gauge and absolute readings on the same scale.

The reference table below the converter gives fixed anchor conversions. Enter any value in the tool for readings not listed on a static chart.

Hydraulic head (pressure from a column of fluid in metres) depends on fluid density — use ρgh, not a simple unit factor. Gauge kPa (kPag) differs from absolute kPa by roughly 101.3 kPa at sea level — note the reference on datasheets.

For everyday tasks — tyres, scuba tanks, espresso machines, industrial compressors, and lab vacuum — PSI, bar, kPa, and mmHg conversions on this page cover the units in the dropdowns with standard factors.