PSI to atm Converter
Instantly convert pounds per square inch to atmospheres, kilopascals, bar, mmHg, inHg, kgf/cm², and more — with live precision control, quick presets for common tire & system pressures, composite atm & psi display, and a downloadable PDF report.
Uses standard atmospheres: 1 atm = 14.6959 psi = 101,325 Pa, so 1 psi = 0.068046 atm and 1 psi = 6.89476 kPa — for reference only.
| PSI | Atmospheres | Kilopascals | Bar |
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PSI to atm Conversion — Complete Guide for 2026
Converting psi (pounds per square inch) to atm (standard atmospheres) connects everyday US pressure readings with the scientific unit based on the air around us. Tire gauges, water-pressure tests, air compressors, and scuba tanks read in psi, while chemistry, physics, diving, and weather science often express pressure in atmospheres. The key relationship is: 1 atm = 14.6959 psi, so 1 psi ≈ 0.068046 atm — and 1 psi ≈ 6.895 kPa.
Our free PSI to atm Converter takes a pressure in psi and returns atmospheres at 0 to 8 decimal places, splits the result into whole atmospheres plus leftover psi (30 psi becomes 2 atm 0.61 psi), and converts across the pressure ladder — kilopascals, bar, mmHg (torr), inHg, and kgf/cm². Quick presets, a log-scale comparison chart, a common-pressures reference table, and a downloadable PDF report make it useful for a quick check or for class, lab, and equipment records.
How to Use the PSI to atm Converter in 4 Steps
A complete psi-to-atm conversion takes a few seconds. Enter a pressure or tap a preset, choose your precision, and download a PDF report you can keep with a lab write-up, maintenance log, or equipment file.
Enter the Pressure in PSI
Type any pressure in psi — a tire gauge reading, a water-pressure test, or an equipment rating. Decimals are supported, from a fraction of a psi to thousands of psi for cylinders and hydraulics, and the result updates on every keystroke.
Or Tap a Quick Preset
Common pressures are one tap away: 14.7 psi (1 atm), 30 and 32 psi (car tires), 45 and 60 psi (household water), and 100 psi (compressors and road bikes). The active preset stays highlighted, and typing a matching value re-selects it automatically.
Set Decimal Precision
Use the input or slider to pick 0 to 8 decimal places for the atm result (the default is 4). Two decimals are plenty for tires and household systems; four or more suit chemistry, physics, and technical records.
Review & Download PDF
See your pressure in atmospheres, kilopascals, atm-and-psi, psi, bar, mmHg, inHg, and kgf/cm², plus a chart comparing the numbers. Click Download PDF for a two-page branded report with every conversion, the chart, and a highlighted reference table.
Why 1 atm = 14.6959 PSI
The standard atmosphere (atm) represents typical air pressure at sea level. It was originally tied to the height of a mercury column — 760 millimeters — and is now defined as exactly 101,325 pascals. The psi is a US customary unit: one pound of force spread over one square inch, which works out to about 6,894.757 pascals.
Dividing one by the other gives 1 atm = 14.6959 psi, usually rounded to 14.7. In plain terms, the air around you presses on every square inch of surface with a force of roughly 14.7 pounds — you don’t notice it because it pushes equally from all sides. The calculator converts through pascals using these defined constants, so there is no rounding drift between units.
Gauge pressure vs absolute pressure
With psi and atmospheres, it matters where you start counting from:
- Gauge pressure (psig) — measured relative to the surrounding air. Tire, water, and compressor gauges read zero when open to the air.
- Absolute pressure (psia) — measured from a perfect vacuum. At sea level, psia = psig + 14.696.
- Atmospheres — often used as an absolute unit in science (a sealed jar at room air is at 1 atm), but you can express gauge pressure in atm too — just label it.
A tire at 32 psi on the gauge holds air at about 2.18 atm above the outside air — or about 3.18 atm absolute. Mixing the two is the most common psi-to-atm mistake, and it’s always off by almost exactly 1 atm. Because the conversion itself is precise, the real uncertainty is which kind of pressure you started with.
What the PSI to atm Converter Calculates
More than a single atm figure — the tool gives you a complete pressure breakdown across US customary, SI, mercury-column, and older metric units, formatted for tires, science, equipment, or reports.
Atmospheres (Hero Result)
The headline result divides your psi by 14.6959 and shows it at the precision you select, with a summary line beneath it that also gives kilopascals and the atm-and-psi split.
Kilopascals & Bar
Kilopascals (psi × 6.895) and bar (psi × 0.0689) are the metric units on vehicle placards, European equipment, and engineering documents, so you can match any metric spec at a glance.
Atmospheres & PSI (Composite)
The result is split into whole atmospheres plus leftover psi — 30 psi becomes 2 atm 0.61 psi. That makes it easy to see how many “atmospheres’ worth” of pressure a reading represents.
mmHg & inHg
Millimeters of mercury (1 atm = 760 mmHg) and inches of mercury (1 atm ≈ 29.92 inHg) cover barometers, weather reports, vacuum work, and laboratory measurements based on the classic mercury column.
kgf/cm²
Kilogram-force per square centimeter (1 kgf/cm² ≈ 14.223 psi), often written kg/cm², still appears on some gauges, compressors, and equipment in parts of Asia and on older machinery.
Chart, Reference Table & PDF
A log-scale bar chart compares your value in psi, atm, kPa, bar, and mmHg so very different magnitudes fit on one view. A reference table of common pressures highlights your input when it matches, and the two-page PDF bundles everything for sharing or record-keeping.
PSI to atm Conversion Chart — Common Pressures
Bookmark this page or screenshot the table below for instant reference. Every value uses 1 atm = 101,325 Pa and 1 psi = 6,894.757 Pa, rounded to four decimals for atm and bar. Tire, water, and equipment readings are gauge pressures; examples are typical figures that vary by vehicle, system, and manufacturer.
| PSI | Atmospheres | Kilopascals | Bar | Common Use |
|---|---|---|---|---|
| 1 psi | 0.0680 atm | 6.895 kPa | 0.0689 bar | Very low pressure |
| 5 psi | 0.3402 atm | 34.474 kPa | 0.3447 bar | Low-pressure air or gas systems |
| 12.2 psi | 0.8302 atm | 84.116 kPa | 0.8412 bar | Air pressure near 5,000 ft (approx.) |
| 14.696 psi | 1.0000 atm | 101.325 kPa | 1.0133 bar | 1 standard atmosphere (sea level) |
| 20 psi | 1.3609 atm | 137.895 kPa | 1.3790 bar | Lawn and garden equipment tires |
| 30 psi | 2.0414 atm | 206.843 kPa | 2.0684 bar | Car tire (lower range) |
| 32 psi | 2.1775 atm | 220.632 kPa | 2.2063 bar | Car tire (typical) |
| 35 psi | 2.3816 atm | 241.317 kPa | 2.4132 bar | Car tire (upper range) |
| 40 psi | 2.7218 atm | 275.790 kPa | 2.7579 bar | Household water (lower range) |
| 60 psi | 4.0828 atm | 413.685 kPa | 4.1369 bar | Household water (typical) |
| 80 psi | 5.4437 atm | 551.581 kPa | 5.5158 bar | Common household plumbing limit |
| 100 psi | 6.8046 atm | 689.476 kPa | 6.8948 bar | Road bike tire or air compressor |
| 150 psi | 10.2069 atm | 1,034.214 kPa | 10.3421 bar | Shop air compressor (max, typical) |
| 3,000 psi | 204.1379 atm | 20,684.272 kPa | 206.8427 bar | Scuba cylinder (typical fill) |
How to Use PSI and Atmospheres in Real Situations
The most common reasons people convert psi to atm are science problems, understanding tire and equipment pressure in terms of “atmospheres,” and making sense of how altitude and water depth change pressure. Each one depends on knowing whether a reading is gauge or absolute.
The manual calculation
Step 1: Decide whether you need gauge or absolute pressure. Step 2: For absolute, add 14.696 psi (at sea level) to a gauge reading. Step 3: Divide by 14.6959 for atmospheres. For a car tire reading 32 psi on the gauge:
Absolute: 32 + 14.696 = 46.696 psia
46.696 psia ÷ 14.6959 = 3.1775 atm absolute
Result: about 2.18 atm gauge, or about 3.18 atm absolute
Enter the gauge reading into the calculator for the gauge result, or enter the absolute psi (gauge + 14.696) for the absolute result. The calculator converts whatever number you give it — it’s up to you to know which kind of pressure it is. For metric units, see our Bar to kPa Converter.
Pressure changes you can feel
Atmospheres make it easy to picture how pressure changes around you:
- Altitude — air pressure is about 1 atm (14.7 psi) at sea level, roughly 0.83 atm near 5,000 ft, and roughly 0.69 atm near 10,000 ft in the standard atmosphere model.
- Water depth — in seawater, pressure rises by about 1 atm for every 33 ft (10 m) of depth; at 33 ft, a diver is at about 2 atm absolute.
- Household water — typical US water pressure of 40–80 psi is roughly 2.7–5.4 atm above ambient.
- Weather — normal barometric swings are only a few percent of an atmosphere, which is why forecasts use finer units like inHg or hPa.
PSI to atm — Key Conversion Numbers
The PSI to atm Converter Is Built For You If…
Whether you’re checking tire pressure, testing your home’s water supply, or solving a gas-law problem — this calculator gives you the exact answer in seconds, with a report you can save and share.
Drivers & Cyclists
Tires & altitudeTire pressure is read in psi on US gauges, but it’s easier to picture as “about two atmospheres above the outside air.” Converting helps you understand what the gauge means and why readings shift with temperature and altitude.
- 32 psi on the gauge ≈ 2.18 atm above ambient
- Use the door-jamb placard, not the sidewall maximum
- Check tires cold — heat raises the reading
- Readings rise slightly when you drive to higher elevation
Homeowners & DIYers
Water, compressors & tanksWater-pressure gauges, well-tank pressure switches, air compressors, and pressure washers are rated in psi — while imported equipment may use atm, bar, or kg/cm². Converting helps you compare specs and understand inspection reports.
- 40–80 psi ≈ 2.7–5.4 atm for typical household water
- Many codes call for a pressure-reducing valve above 80 psi
- kg/cm² gauges read close to, but not exactly, atm
- Keep the PDF with inspection or service records
Students, Divers & Technicians
Science & specificationsGas laws, diving tables, and lab procedures often use atmospheres, while US equipment reads psi. An exact converter — with a clear view of gauge vs absolute — keeps calculations correct and records consistent.
- Use absolute pressure in gas-law formulas
- ≈ 1 atm per 33 ft (10 m) of seawater
- Label every reading psig or psia
- Attach the PDF to lab or service reports
7 Tips for Accurate PSI to atm Conversions
The conversion is fixed, but pressure readings are easy to misinterpret. Most mistakes come from mixing gauge and absolute pressure, rounding too far, confusing similar units, and ignoring altitude. These rules keep every conversion trustworthy.
Know Gauge vs Absolute
Everyday gauges read psig (above the surrounding air). Science often uses absolute pressure. At sea level, add 14.696 psi — exactly 1 atm — to convert gauge to absolute before dividing.
Use 14.696, Not 15
Dividing by 15 instead of 14.696 understates atmospheres by about 2%. Use 14.7 for quick estimates and 14.6959 (or the calculator) for homework, lab work, and specifications.
Bar, atm, and kg/cm² Aren’t Equal
They’re close but not interchangeable: 1 atm = 1.01325 bar = 1.0332 kgf/cm². Treating them as the same introduces errors of 1–3%, which matters in calibration and technical work.
Account for Altitude
Local air pressure drops with elevation, so 1 atm is a sea-level reference, not your local pressure. Gauge readings are relative to local air; absolute calculations at altitude should use local atmospheric pressure.
Don’t Mix Up psi, psf, and ksi
Psi is pounds per square inch; psf (pounds per square foot, 144 psf = 1 psi) is used for building loads like snow and decks; ksi (1,000 psi) is used for material strength. A unit mix-up can be off by a factor of 144 or 1,000.
Check Tires Cold, Use the Placard
Tire pressure rises as tires warm up. Measure before driving, and inflate to the vehicle placard value — not the maximum printed on the sidewall, which is a limit, not a target.
Memorize Three Anchors for Mental Math
1 atm ≈ 14.7 psi ≈ 101 kPa ≈ 1 bar. 1 psi ≈ 0.068 atm ≈ 6.9 kPa. 1 atm ≈ 33 ft of seawater. With these you can check any reading in your head — 60 psi is about 4 atm, and 100 psi is about 6.8 atm.
PSI to atm Converter — Frequently Asked Questions
Everything you need to know about converting psi to atmospheres, the difference between gauge and absolute pressure, and how pressure changes with altitude and depth.
One psi equals about 0.068046 standard atmospheres. The standard atmosphere is defined as exactly 101,325 pascals, and one psi is about 6,894.757 pascals, so 1 atm = 14.6959 psi and 1 psi = 1 ÷ 14.6959 ≈ 0.068046 atm.
Divide psi by 14.6959: atm = psi ÷ 14.6959, which is the same as atm = psi × 0.068046. For example, 30 psi = 2.0414 atm, 60 psi = 4.0828 atm, and 100 psi = 6.8046 atm. To go from atmospheres back to psi, multiply by 14.6959.
Multiply atmospheres by 14.6959: psi = atm × 14.6959. For example: 1 atm = 14.696 psi, 2 atm = 29.392 psi, 5 atm = 73.480 psi, and 10 atm = 146.959 psi. This converter takes psi as its input; to check a result, enter the psi figure you calculated and confirm the atm result matches.
The standard atmosphere represents average air pressure at sea level and is defined as exactly 101,325 pascals. A psi — one pound-force on one square inch — is about 6,894.757 pascals. Dividing gives 101,325 ÷ 6,894.757 ≈ 14.6959 psi, usually rounded to 14.7 psi. In other words, the air around you presses on every square inch with a force of about 14.7 pounds.
Psig (gauge) is pressure measured relative to the surrounding air, so an open gauge reads zero; tire and water gauges read psig. Psia (absolute) is measured relative to a perfect vacuum. At sea level, psia = psig + 14.696. Plain psi usually means gauge pressure in everyday use, but scientific atm values are often absolute, so check which one a figure means before converting.
A tire gauge reading of 32 psi means 32 psi above the surrounding air, which is about 2.18 atm of gauge pressure. In absolute terms, the air inside the tire is at about 46.7 psia, or roughly 3.18 atm, because the atmosphere’s own 1 atm is added on top of the gauge reading.
One psi equals about 6.895 kilopascals or 0.0689 bar. For example, 32 psi is about 220.6 kPa or 2.21 bar. Going the other way, 1 bar equals about 14.504 psi, and 1 atm equals 101.325 kPa or 1.01325 bar.
Air pressure falls as you climb. In the standard atmosphere model, pressure is about 14.7 psi (1 atm) at sea level, roughly 12.2 psi (about 0.83 atm) near 5,000 feet, and roughly 10.1 psi (about 0.69 atm) near 10,000 feet. Actual pressure also varies with weather. Because tire gauges read relative to local air, a tire’s gauge reading rises slightly when you drive to a higher elevation.
One standard atmosphere equals 760 mmHg (millimeters of mercury) and about 29.92 inHg (inches of mercury). One psi equals about 51.715 mmHg or 2.036 inHg. US weather reports and barometers often use inHg, while laboratories, vacuum work, and blood-pressure readings use mmHg.
Kgf/cm² (kilogram-force per square centimeter), often written kg/cm², is an older metric pressure unit still seen on some gauges and equipment, especially in parts of Asia. One kgf/cm² equals exactly 98.0665 kPa, which is about 14.223 psi or 0.968 atm. It is close to, but not the same as, one atmosphere or one bar.
In seawater, pressure increases by about 1 atm (roughly 14.7 psi) for every 33 feet, or about 10 meters, of depth. At 33 feet down, a diver experiences about 2 atm absolute — 1 atm from the air above plus about 1 atm from the water. Fresh water is slightly less dense, so it takes a little more depth to add 1 atm.
The converter uses defined constants: 1 atm = 101,325 Pa; 1 psi = 6,894.757 Pa; 1 mmHg = 133.322 Pa; 1 inHg = 3,386.389 Pa; and 1 kgf/cm² = 98,066.5 Pa. Calculations use double-precision floating-point arithmetic, and display precision is adjustable from 0 to 8 decimal places. In practice, accuracy is limited by the gauge you read and by whether it shows gauge or absolute pressure, not by the conversion.
Accuracy note: The HomeExpertly PSI to atm Converter uses the defined standard atmosphere: 1 atm = 101,325 pascals and 1 psi = 6,894.757 pascals, so 1 atm = 14.6959 psi, together with 1 mmHg = 133.322 Pa, 1 inHg = 3,386.389 Pa, and 1 kgf/cm² = 98,066.5 Pa, consistent with the International System of Units (SI) and values recognized by the U.S. National Institute of Standards and Technology (NIST). All calculations are mathematically precise to the decimal precision you select (up to 8 places). However, results are for informational and reference purposes only. Most everyday gauges show gauge pressure (psig), not absolute pressure, and actual atmospheric pressure varies with altitude and weather. Tire, water, compressor, cylinder, altitude, and diving figures on this page are typical or approximate values that vary by vehicle, system, manufacturer, location, and conditions. This page is not a diving or medical guide. For applications where pressure is critical — including but not limited to tire inflation, plumbing and well systems, compressed-gas cylinders, diving, laboratory work, or code compliance — always follow manufacturer specifications and applicable standards, use calibrated gauges, and consult a qualified professional. HomeExpertly is not responsible for any consequences arising from the use of these conversions.