Here's a small confession: pressure is the measurement that humbles almost everyone at some point. You check your tires and the gauge says 32, but the sticker inside the door says 220. Your doctor tells you your blood pressure is 120 over 80, then a European medical report shows the same reading as 16 kilopascals. A weather presenter mentions 1013 millibars while a pilot two miles overhead is dialing 29.92 into an altimeter. All of these numbers describe the exact same physical thing — force pressing on a surface — yet they live in different unit systems that grew up in different centuries, industries, and countries.
That's precisely why we built the Pressure Unit Converter you see above. It's a free online pressure conversion calculator that translates instantly between 26 pressure units — bar, psi, pascal, kilopascal, atm, mmHg, torr, inHg, kgf/cm² and more — in six languages, right inside this page, with no downloads, no sign-ups, and nothing sent to any server. This article is the complete companion guide: what pressure actually is, what every one of those 26 units means, the exact conversion formulas the tool uses under the hood, quick-reference tables you can bookmark, worked examples, real-world use cases, and honest answers to the questions people ask us most.
Grab a coffee (brewed, incidentally, at about 9 bar of pressure) and let's make sense of it all.
Pressure Unit Converter Embed Code for Your Website:
Pressure is the silent force that surrounds us every moment – it's the air we breathe pressing down on our shoulders, the water deep in the ocean pushing against the hulls of submarines, the steam powering mighty engines, and the gentle touch of a tire meeting the road. Yet, pressure speaks in many dialects. A pascal whispers the story of a gentle breeze, a bar captures the weight of the atmosphere, and PSI tells the tale of industrial might. This tool was created to help everyone understand the invisible forces that shape our physical world.
You can copy this code and embed it on your website, offering your visitors a thoughtful, practical companion that illuminates how they think about pressure and force. Whether they're checking tire pressure before a road trip, studying weather patterns, designing hydraulic systems, diving into the depths of the ocean, or simply curious about how different pressure units relate to one another, this Pressure Unit Converter turns complex comparisons into simple, intuitive understanding.
The Pressure Unit Converter is an elegantly simple, interactive tool that allows your website visitors to instantly convert between pascals (Pa), bars, pounds per square inch (psi), atmospheres (atm), torr, and more. Simply enter a value in any unit, and watch as all other units update in perfect harmony – transforming what could be a confusing technical exercise into a moment of effortless clarity.
This tool is essential for automotive and engineering blogs, weather and meteorology websites, scuba diving and marine platforms, industrial and manufacturing resources, scientific education sites, or any space where pressure and force play a meaningful role. It's more than a converter – it's a bridge that connects people across different measurement traditions and ways of understanding the invisible forces that surround us.
The code is available in six global languages to welcome visitors from every corner of the earth: English - Spanish - French - Arabic - Chinese - Hindi.
You can easily switch the converter language by changing the parameter in the URL: ?lang=en
Available languages: en - es - fr - ar - zh - hi
1- Isolated iFrame Code (Ideal for Articles and Pages):
If you're writing about weather phenomena, engineering marvels, automotive maintenance, deep-sea exploration, or scientific discoveries, this method allows you to embed the tool directly within your content. The isolated iframe ensures a clean, focused experience, so your readers can experiment with pressure conversions alongside your insights – connecting the numbers to the real-world forces that make pressure such a fascinating and essential subject.
<iframe id="tq_pressure_converter" src="https://tools.tooliqo.co/pressure-converter/?lang=en" title="Tooliqo" loading="lazy" scrolling="no" style="width:100%;max-width:100%;height:672px;border:0;overflow:hidden;display:block;margin:0 auto;"></iframe>
<script>(function(){var i="tq_pressure_converter",b="https://tools.tooliqo.co/pressure-converter/",dl="en";function L(){try{var h=(document.documentElement.getAttribute("lang")||"").toLowerCase();var ok=["ar","en","fr","es","zh","hi"];for(var k=0;k<ok.length;k++){if(h.indexOf(ok[k])===0)return ok[k];}}catch(e){}return dl;}function R(){var f=document.getElementById(i);if(!f)return;var lg=L();if(lg){var want=b+"?lang="+lg;if((f.getAttribute("src")||"").indexOf("lang="+lg)===-1)f.setAttribute("src",want);}window.addEventListener("message",function(e){var d=e.data;if(!d||typeof d.tqHeight!=="number"||d.tqHeight<50)return;try{if(f.contentWindow&&e.source&&e.source!==f.contentWindow)return;}catch(x){}f.style.height=(d.tqHeight+20)+"px";},false);}if(document.readyState==="loading"){document.addEventListener("DOMContentLoaded",R);}else{R();}})();</script>
2- Flexible Script (Suitable for Sidebars and Templates):
This method is perfect for sidebars, footers, or widget areas where you want the tool to be always within reach. The converter loads smoothly and gracefully, becoming a trusted companion that helps your visitors navigate the world of pressure – whether they're checking weather forecasts, maintaining their vehicles, planning a diving expedition, or simply exploring the fascinating relationships between different units of pressure measurement.
Just add these lines to your website's code, and the Pressure Unit Converter will appear instantly, ready to help. It's fully responsive by design, offering a flawless experience on desktops, tablets, and mobile phones.
<div class="tooliqo-tool" data-tool="pressure-converter" data-lang="en"></div> <script src="https://tools.tooliqo.co/embed.js" async></script>
Note: The Pressure Unit Converter works in real-time, instantly updating all units as your visitors type or adjust values. No page reloads needed – just a smooth, intuitive experience that makes pressure feel less like an abstract concept and more like something we can all understand and appreciate. Because when we understand pressure better, we connect more deeply with the invisible forces that shape our world – from the air we breathe to the depths we explore.
What Is Pressure, Really?
Strip away the jargon and pressure is a simple idea: force divided by the area it's spread across. Physicists write it as:
P = F / A
where P is pressure, F is force, and A is area. Push your thumb against a wall and nothing happens. Push a thumbtack with the same force and it sinks in — same force, tiny area, enormous pressure. That one equation explains why snowshoes keep you on top of snow, why sharp knives cut better than dull ones, and why a woman in stiletto heels can dent a hardwood floor that an elephant's foot would not.
In the International System of Units (SI), force is measured in newtons and area in square meters, so pressure comes out in newtons per square meter — a unit the world renamed the pascal (Pa) in 1971 in honor of Blaise Pascal, the 17th-century French genius who proved that atmospheric pressure drops as you climb a mountain. One pascal is tiny: a single sheet of paper lying flat on a table presses down with roughly one pascal. The air around you right now presses on your skin with about 101,325 pascals — you don't feel it because it pushes equally from every direction, and your body pushes back.
Because the pascal is so small and the atmosphere so influential, dozens of practical units emerged over three centuries: mercury columns from early barometers, water columns from plumbing and ventilation work, pounds per square inch from British and American engineering, the bar from European meteorology, kilogram-force units from the old metric-technical system. None of them is wrong. They're just different dialects of the same language — and a good converter is your interpreter.
Gauge, Absolute, and Differential Pressure — the Distinction That Saves You From Mistakes
Before converting anything, know what your number is measured against. This matters more than any unit conversion:
- Absolute pressure is measured against a perfect vacuum. Weather reports, vacuum chambers, and scientific formulas use absolute pressure. Sea-level air is about 1 atm absolute.
- Gauge pressure is measured against the surrounding atmosphere. Your tire gauge reads zero in open air, so "32 psi" on a tire really means 32 psi above atmospheric — roughly 46.7 psi absolute.
- Differential pressure is simply the difference between two points — across a filter, a valve, or a hospital isolation-room doorway.
A unit converter — ours included — translates units, not reference points. If a datasheet says psia (absolute) and your gauge reads psig (gauge), convert the reference first, then the unit. We'll come back to this in the mistakes section, because it's the single most common source of pressure errors in the real world.
A Two-Minute History: From Torricelli's Mercury Tube to Your Browser
In 1643, Evangelista Torricelli sealed mercury in a glass tube, flipped it into a dish, and watched the column settle at about 760 millimeters no matter how he tilted the tube. He had built the first barometer and, without quite intending to, invented the first pressure unit: the millimeter of mercury. Pascal soon sent his brother-in-law up the Puy de Dôme with one of these tubes to show that the column fell with altitude — proof that we live at the bottom of an ocean of air.
For the next 300 years, every industry that needed pressure invented a unit that matched its instruments. Doctors kept the mercury millimeter because sphygmomanometers literally contained mercury. American engineers, working in pounds and inches, standardized on psi. Meteorologists adopted the bar and millibar because they made atmospheric numbers tidy. Vacuum scientists honored Torricelli with the torr. HVAC technicians measured tiny duct pressures with water-filled manometers, giving us inches and millimeters of water. The result is today's beautiful mess — 26 units and counting — which is exactly the mess this tool exists to untangle.
Meet the Tooliqo Pressure Unit Converter: What Makes It Different
There are plenty of pressure converters online. We built ours because we kept running into the same frustrations everywhere else: cluttered pages, ten ads per conversion, no Arabic or Chinese interface, rounding errors from chained conversions, and unit lists so long and disorganized you needed a search box to find psi. Here's what we did differently, and it's all live in the tool above:
- 26 units organized into 6 logical families. Metric (SI), bar units, atmosphere & force units, mercury column, water column, and imperial (US). You'll find any unit in two seconds because it's grouped where your intuition expects it.
- Truly instant conversion. There is no Convert button. Type, and the answer is already there. Change a unit, and every number on screen updates — the main result, the formula line, and the equivalents panel.
- One-tap swap. The arrows button between the two menus reverses the direction of conversion instantly — bar to psi becomes psi to bar without re-selecting anything.
- Six full languages. English, Arabic, French, Spanish, Chinese, and Hindi — and not just the buttons: all 26 unit names are translated, and Arabic gets a complete right-to-left layout. The tool detects your language automatically and remembers your choice.
- A common-equivalents panel. Whatever you convert, the tool also shows your value in kPa, bar, psi, atm, mmHg, and inHg simultaneously — because half the time you need two or three units at once, not one.
- A live formula line. Under every result you'll see the exact relationship, such as 1 bar = 14.503774 psi, so you learn the conversion factor while you use it.
- Forgiving input. Type 1.5 or 1,5 — both work. Paste values with spaces. Use Eastern Arabic numerals. Negative values and scientific notation are fine too.
- Honest precision. Every conversion pivots through the pascal in a single double-precision calculation using exact SI definitions and internationally accepted conventional factors, displayed to up to 11 significant digits, with automatic scientific notation for extreme values.
- Copy button. One tap puts the result on your clipboard, ready for a spreadsheet, report, or homework answer.
- Shareable links. You can link a colleague straight to a preloaded conversion — for example, five bar to psi in Spanish — by adding simple parameters to the tool's address.
- Private and featherweight. Everything computes in your browser. Nothing you type ever leaves your device, and the tool weighs less than a single photo, so it loads instantly even on slow mobile connections.
How to Use It in Under 30 Seconds
- Type a value in the input box at the top of the tool.
- Pick your source unit in the From menu — the six family groups keep the list short and scannable.
- Pick your target unit in the To menu. The result appears immediately, big and bold.
- Swap direction with the middle button whenever you need the reverse conversion.
- Copy the result, or glance at the equivalents panel for five more units at once.
- Change language from the selector in the header if you prefer Arabic, French, Spanish, Chinese, or Hindi.
All 26 Pressure Units Explained, Family by Family
1. Metric (SI) Units — the Scientific Backbone
Pascal (Pa). The official SI unit: one newton per square meter. Perfect for physics, comically small for daily life — atmospheric pressure is over one hundred thousand of them.
Hectopascal (hPa). Exactly 100 Pa. Meteorology's favorite trick: 1 hPa equals 1 millibar precisely, so when weather services went metric, every historical chart stayed numerically identical. Standard sea-level pressure: 1013.25 hPa.
Kilopascal (kPa). 1,000 Pa — the practical everyday metric unit. Tire placards across Europe, Asia, and Australia, food-packaging specs, and building codes all speak kPa. One atmosphere is 101.325 kPa.
Megapascal (MPa). A million pascals, and the language of engineers. Concrete is crushed at 25–50 MPa, structural steel yields around 250–550 MPa, and hydraulic presses are rated in MPa. Handy anchor: 1 MPa = 10 bar ≈ 145 psi.
Gigapascal (GPa). A billion pascals — the realm of material stiffness (steel's elastic modulus is about 200 GPa), diamond anvils, and planetary cores. Earth's center sits near 360 GPa.
Newton per square meter (N/m²) and kilonewton per square meter (kN/m²). Identical to the pascal and kilopascal, but textbooks, exams, and geotechnical reports (soil bearing capacity, floor loading) write them this way, so the tool includes both spellings.
2. Bar Units — Europe's Industrial Standard
Bar. Defined as exactly 100,000 Pa, deliberately within 1.3% of one atmosphere. Scuba tanks (200–300 bar), air compressors, hydraulic circuits, espresso machines (9 bar), and European tire gauges all run on bar.
Millibar (mbar). One-thousandth of a bar. The classic weather unit — hurricane hunters still report central pressures like 915 mbar, and vacuum equipment specs frequently use mbar.
Microbar (µbar). One-millionth of a bar (0.1 Pa), found in acoustics and fine vacuum work.
3. Atmosphere & Force Units — the Historical Heavyweights
Standard atmosphere (atm). Exactly 101,325 Pa by international agreement — the average sea-level pressure that chemistry, diving tables, and gas-law problems are built on.
Technical atmosphere (at). Exactly one kilogram-force per square centimeter, i.e. 98,066.5 Pa — about 3.3% less than the standard atmosphere. Old European machine manuals love this unit, and confusing "at" with "atm" is one of the classic conversion traps.
Kilogram-force per square centimeter (kgf/cm²). Numerically identical to the technical atmosphere. Walk through any industrial site in Asia or Latin America and you'll still see gauges marked kgf/cm². Anchor: 1 kgf/cm² ≈ 14.22 psi ≈ 0.981 bar.
Kilogram-force per square meter (kgf/m²). Just 9.80665 Pa — used for gentle pressures in ventilation and ductwork.
Dyne per square centimeter (dyn/cm²), the barye. The old CGS-system unit, exactly 0.1 Pa, still alive in acoustics and astrophysics papers.
4. Mercury Column Units — Medicine and the Sky
Torr. Defined as exactly 1/760 of a standard atmosphere, honoring Torricelli. The vacuum industry's native tongue: rough vacuum, high vacuum, ultra-high vacuum — all specified in torr.
Millimeter of mercury (mmHg). Conventionally 133.322387415 Pa — so close to the torr that they differ by less than one part in seven million, yet formally distinct. Medicine standardized on mmHg: blood pressure, eye pressure, ventilator settings.
Centimeter of mercury (cmHg). Ten millimeters of mercury; occasionally used in physiology and older literature.
Inch of mercury (inHg). About 3,386.39 Pa. American weathercasts ("barometer at 30.12 inches") and aviation altimeter settings (standard: 29.92 inHg) keep this unit very much alive.
5. Water Column Units — the Low-Pressure Specialists
When pressures are tiny, a mercury column barely moves — but a water column, mercury being 13.6 times denser, moves visibly. That's why low-pressure trades adopted water units.
Millimeter of water (mmH₂O) — 9.80665 Pa, for fan pressures and medical suction. Centimeter of water (cmH₂O) — 98.0665 Pa, the universal unit of CPAP machines and ventilator PEEP settings; if you or a family member uses a CPAP set to "10", that's 10 cmH₂O. Inch of water (inH₂O) — about 249.09 Pa, North American HVAC's unit for duct static pressure and filter pressure drop. Foot of water (ftH₂O) — about 2,989.07 Pa, the pump engineer's "head" unit for wells and municipal water systems.
6. Imperial (US) Units — Pounds and Inches
Pound per square inch (psi). 6,894.757 Pa, and arguably the most-typed pressure unit on the internet. American tires (30–35 psi), garden hoses (40–60 psi), air compressors, and paintball tanks all speak psi.
Kilopound per square inch (ksi). 1,000 psi, engineering shorthand — US steel grades are quoted like "50 ksi yield."
Pound per square foot (psf). About 47.88 Pa. American structural codes express floor live loads, wind loads, and snow loads in psf.
The Master Table: Every Unit's Exact Value in Pascals
This is the same table the converter uses internally. Every conversion is just two steps through this column: multiply by the From value, divide by the To value.
| Unit | Symbol | Value in pascals (Pa) |
|---|---|---|
| Pascal | Pa | 1 (exact) |
| Hectopascal | hPa | 100 (exact) |
| Kilopascal | kPa | 1,000 (exact) |
| Megapascal | MPa | 1,000,000 (exact) |
| Gigapascal | GPa | 1,000,000,000 (exact) |
| Newton per square meter | N/m² | 1 (exact) |
| Kilonewton per square meter | kN/m² | 1,000 (exact) |
| Microbar | µbar | 0.1 (exact) |
| Millibar | mbar | 100 (exact) |
| Bar | bar | 100,000 (exact) |
| Standard atmosphere | atm | 101,325 (exact) |
| Technical atmosphere | at | 98,066.5 (exact) |
| Kilogram-force per square centimeter | kgf/cm² | 98,066.5 (exact) |
| Kilogram-force per square meter | kgf/m² | 9.80665 (exact) |
| Dyne per square centimeter (barye) | dyn/cm² | 0.1 (exact) |
| Torr | Torr | 101,325 ÷ 760 ≈ 133.322368 |
| Millimeter of mercury | mmHg | 133.322387415 (conventional) |
| Centimeter of mercury | cmHg | 1,333.22387415 (conventional) |
| Inch of mercury | inHg | 3,386.38815789 (conventional) |
| Millimeter of water | mmH₂O | 9.80665 (conventional) |
| Centimeter of water | cmH₂O | 98.0665 (conventional) |
| Inch of water | inH₂O | 249.088908 (conventional) |
| Foot of water | ftH₂O | 2,989.0669 (conventional) |
| Pound per square inch | psi | 6,894.757293168 |
| Kilopound per square inch | ksi | 6,894,757.293168 |
| Pound per square foot | psf | 47.880258980 |
The Essential Conversion Formulas (the Same Ones the Tool Shows You)
These are the "1 unit = …" relationships the converter displays under every result. Memorize the first four and you'll handle 90% of daily pressure conversions in your head:
- 1 bar = 14.503774 psi — and 1 psi = 0.0689476 bar
- 1 bar = 100 kPa = 0.986923 atm
- 1 atm = 101.325 kPa = 1.01325 bar = 14.6959 psi = 760 Torr = 29.9213 inHg
- 1 MPa = 10 bar = 145.0377 psi
- 1 psi = 6.894757 kPa = 51.7149 mmHg = 27.6799 inH₂O
- 1 kgf/cm² = 0.980665 bar = 14.2233 psi = 1 at (exactly)
- 1 inHg = 33.8639 hPa = 25.4 mmHg (exactly) = 0.491154 psi
- 1 mmHg = 0.133322 kPa = 1.35951 cmH₂O
- 1 kPa = 7.50062 mmHg = 4.01463 inH₂O = 0.145038 psi
- 1 ftH₂O = 0.433514 psi = 2.98907 kPa
And the universal two-step method behind all of them: multiply your value by the From unit's pascal factor, then divide by the To unit's pascal factor. One pivot, no chained rounding, no drift.
Quick-Reference Conversion Tables
Bar to PSI (and Back) — Tires, Compressors, Diving
| bar | psi | psi | bar | |
|---|---|---|---|---|
| 0.5 | 7.25 | 10 | 0.69 | |
| 1 | 14.50 | 20 | 1.38 | |
| 1.5 | 21.76 | 29 | 2.00 | |
| 2 | 29.01 | 32 | 2.21 | |
| 2.2 | 31.91 | 35 | 2.41 | |
| 2.5 | 36.26 | 40 | 2.76 | |
| 3 | 43.51 | 60 | 4.14 | |
| 5 | 72.52 | 100 | 6.89 | |
| 10 | 145.04 | 150 | 10.34 | |
| 200 | 2,900.75 | 3,000 | 206.84 |
Mental shortcut: bar × 14.5 = psi. A 2.2 bar tire placard is about 32 psi; a 200 bar scuba tank is about 2,900 psi.
Atmosphere to kPa and Bar — Chemistry and Diving
| atm | kPa | bar | psi |
|---|---|---|---|
| 0.5 | 50.66 | 0.507 | 7.35 |
| 1 | 101.325 | 1.013 | 14.70 |
| 2 | 202.65 | 2.027 | 29.39 |
| 3 | 303.98 | 3.040 | 44.09 |
| 4 | 405.30 | 4.053 | 58.78 |
| 5 | 506.63 | 5.066 | 73.48 |
| 10 | 1,013.25 | 10.133 | 146.96 |
Diver's note: each 10 meters of seawater adds almost exactly 1 atm, so a diver at 30 m experiences about 4 atm absolute — the row for 4 atm above.
mmHg to kPa — Blood Pressure and the Laboratory
| mmHg | kPa | Typical context |
|---|---|---|
| 60 | 8.00 | Low diastolic reading |
| 80 | 10.67 | Normal diastolic |
| 100 | 13.33 | Mean arterial pressure range |
| 120 | 16.00 | Normal systolic |
| 140 | 18.67 | Hypertension threshold (systolic) |
| 760 | 101.32 | Standard atmosphere |
PSI to kPa and MPa — Workshop to Datasheet
| psi | kPa | MPa |
|---|---|---|
| 1 | 6.89 | 0.0069 |
| 14.696 | 101.33 | 0.1013 |
| 32 | 220.63 | 0.2206 |
| 100 | 689.48 | 0.6895 |
| 500 | 3,447.38 | 3.447 |
| 1,000 | 6,894.76 | 6.895 |
| 3,000 | 20,684.27 | 20.684 |
inHg to hPa — Aviation and Weather
| inHg | hPa (= mbar) | Context |
|---|---|---|
| 28.00 | 948.2 | Deep low-pressure system |
| 29.00 | 982.1 | Stormy weather |
| 29.92 | 1,013.2 | Standard altimeter setting |
| 30.50 | 1,032.8 | Strong high-pressure system |
Converting by Hand: Five Worked Examples
Example 1 — European Tire Placard to an American Gauge (bar → psi)
Your door sticker says 2.4 bar. Multiply by 100,000 to get 240,000 Pa; divide by 6,894.757 to get 34.8 psi. Inflate to 35 psi and you're spot on.
Example 2 — Blood Pressure for an International Journal (mmHg → kPa)
A systolic reading of 120 mmHg: 120 × 133.322387 = 15,998.7 Pa = 16.0 kPa. That's why global medical literature writes normal blood pressure as 16.0/10.7 kPa.
Example 3 — Crossing the Atlantic in a Cockpit (inHg → hPa)
ATIS reports the altimeter at 29.92 inHg. 29.92 × 3,386.388 = 101,320.7 Pa ≈ 1,013.2 hPa — the same standard atmosphere, two dialects.
Example 4 — Reading a Legacy Gauge (kPa → kgf/cm²)
A pump spec says 350 kPa but the installed gauge is marked in kgf/cm². 350,000 ÷ 98,066.5 = 3.57 kgf/cm².
Example 5 — Vacuum Chamber Spec (Torr → mbar)
A coating process calls for 5 × 10⁻³ Torr. One torr is 133.322 Pa, so that's 0.6666 Pa; divide by 100 to get 6.7 × 10⁻³ mbar. (The converter handles scientific notation like this automatically.)
Where You'll Actually Use This: Nine Everyday Scenarios
Your car. Placards mix kPa and bar; gauges in North America read psi. Driving 0.4 bar (about 6 psi) under-inflated raises fuel consumption by several percent and wears tire shoulders prematurely — real money lost to a unit mix-up.
The weather. European forecasts speak hPa, American ones inHg, hurricane trackers mbar. When you hear "the barometer is falling," you can now translate it into any dialect.
Aviation. Pilots switch altimeter settings between inHg (North America) and hPa (most of the world) on every transatlantic flight. A wrong setting of 1 inHg corresponds to roughly 1,000 feet of altitude error.
The clinic. Blood pressure in mmHg, CPAP and ventilator pressures in cmH₂O, oxygen cylinders in bar or psi — nurses and respiratory therapists hop between three unit families before lunch.
Diving. Tank pressure in bar (Europe) or psi (US), depth-pressure in atm absolute, dive-computer settings in mbar. Getting these right is not academic underwater.
Engineering and construction. Concrete in MPa, US wind loads in psf, hydraulics in bar, bolt charts in ksi. One bridge file, five unit families.
Heating and cooling. Duct static pressure in inH₂O or Pa, refrigerant gauges in psi or bar, room pressurization in pascals. A clogged filter announces itself as a rising inH₂O reading.
The kitchen. Espresso extraction at 9 bar (about 130 psi), pressure cookers at roughly 1 bar gauge (15 psi) — which is why they cook so fast: water boils at about 120 °C inside.
The lab and the fab. Semiconductor and coating processes live across nine orders of magnitude of vacuum, quoted interchangeably in torr, mbar, and Pa depending on the machine's country of origin.
Five Mistakes That Ruin Pressure Conversions (Learn Them Once)
- Mixing up atm and at. The standard atmosphere (101,325 Pa) and the technical atmosphere (98,066.5 Pa) differ by 3.3%. On a 300 bar system that's a 10 bar error. Our converter lists both, clearly labeled, so you never have to guess.
- Ignoring gauge versus absolute. Converting 32 psi (gauge) to bar gives 2.21 bar gauge — but if a formula needs absolute pressure, you must first add atmospheric (≈14.7 psi) to get 46.7 psia. The converter changes units; you choose the reference.
- Chained rounding. Going bar → atm → psi with two-decimal rounding at each step visibly shifts the answer. Convert once, through pascals, at full precision — which is exactly what the tool does internally.
- Assuming mmHg and Torr are "different enough to matter" — or exactly equal when calibrating. For medicine and daily use, treat them as identical. In metrology, torr is 101,325/760 Pa by definition and conventional mmHg is 133.322387415 Pa; the tool applies each unit's own definition, so even that seventh-decimal difference is honored.
- Forgetting column units are conventional. mmH₂O, inH₂O, mmHg and friends are defined at reference conditions (water at 4 °C, mercury at 0 °C, standard gravity). A real manometer on a hot day reads slightly differently. For unit conversion, always use the conventional factors — the ones in the master table above.
Frequently Asked Questions
How many psi is 1 bar?
1 bar equals 14.503774 psi. For quick mental math, multiply bar by 14.5.
Is 1 bar the same as 1 atmosphere?
Close, but no. 1 bar = 100,000 Pa while 1 atm = 101,325 Pa, so 1 bar = 0.9869 atm. The 1.3% gap matters in science, diving, and calibration.
How do I convert kPa to psi?
Multiply kilopascals by 0.145038. So a 220 kPa tire placard is 220 × 0.145 ≈ 32 psi.
What's the difference between mmHg and Torr?
Practically nothing — less than 0.000015%. Formally, torr is defined as 1/760 atm while mmHg is a conventional mercury-column value. Use either in daily life; the converter respects both definitions exactly.
Why is blood pressure measured in mmHg?
Because the original sphygmomanometers contained an actual column of mercury, and medicine kept the unit even after mercury instruments were phased out. 120/80 mmHg equals 16.0/10.7 kPa.
What is a hectopascal, and why do weather reports use it?
1 hPa = 100 Pa = exactly 1 millibar. Adopting the hectopascal let meteorology go fully SI without renumbering a century of weather records.
How many bar is 1 MPa?
Exactly 10. And 1 MPa = 145.04 psi, which makes MPa ↔ psi one of the most-used engineering conversions.
What is kgf/cm² and is it still used?
Kilogram-force per square centimeter — the force of 1 kg under standard gravity on 1 cm², equal to 98,066.5 Pa or about 14.22 psi. It's officially deprecated but still stamped on countless gauges across Asia, Latin America, and older European plants, which is why we included it.
Does this converter handle very large and very small values?
Yes. From microbars of acoustic pressure to gigapascals at the Earth's core, the tool keeps full double-precision accuracy and switches to scientific notation automatically when numbers get extreme.
Is the tool really free, and what happens to my data?
Completely free, no account, no limits. And nothing happens to your data because there isn't any: every calculation runs locally in your browser and nothing is transmitted or stored.
Can I use it on my phone?
Absolutely. The layout adapts to small screens, the numeric keypad opens automatically, and the tool resizes itself smoothly inside this article as you use it.
Can I link someone to a specific conversion?
Yes — the tool accepts address parameters for the value, both units, and the language, so you can send a colleague a link that opens preloaded with, say, 5 bar to psi in Spanish.
The Bottom Line
Pressure wears more disguises than any other everyday measurement — pascals in the textbook, bar at the dive shop, psi at the gas station, mmHg at the doctor's office, inches of mercury on the evening news. But behind every disguise sits the same simple quantity, and every unit maps exactly onto the pascal, which means every conversion is only ever two arithmetic steps away.
The Tooliqo Pressure Unit Converter above performs those steps instantly, precisely, and in your own language, across 26 units that cover everything from a whisper of acoustic pressure to the crush at the center of the Earth. Bookmark this page for the tables and formulas, use the tool whenever a number arrives in the wrong dialect, and if it saves you time, explore the rest of our free converter suite — weight, volume, distance, temperature, time, power, and energy — at Tooliqo.co. We build these tools to be fast, honest, and genuinely useful, and we're glad you're here.