Pressure • NIST Exact

Bars Atmospheres

bar → atm

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NIST Exact

Based on U.S. National Institute of Standards

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Bars to Atmospheres Formula

To convert from Bars to Atmospheres, you can use the following formula:

Atmospheres = Bars × NaN

This means you need to multiply your Bars value by NaN to get the equivalent value in Atmospheres.

bar → atm Reference Table

bar atm
0.001 bar 0.0009869232667 atm
0.002 bar 0.001973846533 atm
0.003 bar 0.0029607698 atm
0.004 bar 0.003947693067 atm
0.005 bar 0.004934616334 atm
0.006 bar 0.0059215396 atm
0.007 bar 0.006908462867 atm
0.008 bar 0.007895386134 atm
0.009 bar 0.0088823094 atm
0.01 bar 0.009869232667 atm
0.02 bar 0.01973846533 atm
0.03 bar 0.029607698 atm
0.04 bar 0.03947693067 atm
0.05 bar 0.04934616334 atm
0.06 bar 0.059215396 atm
0.07 bar 0.06908462867 atm
0.08 bar 0.07895386134 atm
0.09 bar 0.088823094 atm
0.1 bar 0.09869232667 atm
0.2 bar 0.1973846533 atm
0.3 bar 0.29607698 atm
0.4 bar 0.3947693067 atm
0.5 bar 0.4934616334 atm
0.6 bar 0.59215396 atm
0.7 bar 0.6908462867 atm
0.8 bar 0.7895386134 atm
0.9 bar 0.88823094 atm
1 bar 0.9869232667 atm
1.5 bar 1.4803849 atm
2 bar 1.973846533 atm
2.5 bar 2.467308167 atm
3 bar 2.9607698 atm
3.5 bar 3.454231434 atm
4 bar 3.947693067 atm
4.5 bar 4.4411547 atm
5 bar 4.934616334 atm
5.5 bar 5.428077967 atm
6 bar 5.9215396 atm
6.5 bar 6.415001234 atm
7 bar 6.908462867 atm
7.5 bar 7.4019245 atm
8 bar 7.895386134 atm
8.5 bar 8.388847767 atm
9 bar 8.8823094 atm
9.5 bar 9.375771034 atm
10 bar 9.869232667 atm
11 bar 10.85615593 atm
12 bar 11.8430792 atm
13 bar 12.83000247 atm
14 bar 13.81692573 atm
15 bar 14.803849 atm
16 bar 15.79077227 atm
17 bar 16.77769553 atm
18 bar 17.7646188 atm
19 bar 18.75154207 atm
20 bar 19.73846533 atm
25 bar 24.67308167 atm
30 bar 29.607698 atm
35 bar 34.54231434 atm
40 bar 39.47693067 atm
45 bar 44.411547 atm
50 bar 49.34616334 atm
55 bar 54.28077967 atm
60 bar 59.215396 atm
65 bar 64.15001234 atm
70 bar 69.08462867 atm
75 bar 74.019245 atm
80 bar 78.95386134 atm
85 bar 83.88847767 atm
90 bar 88.823094 atm
95 bar 93.75771034 atm
100 bar 98.69232667 atm
120 bar 118.430792 atm
125 bar 123.3654083 atm
130 bar 128.3000247 atm
140 bar 138.1692573 atm
150 bar 148.03849 atm
160 bar 157.9077227 atm
175 bar 172.7115717 atm
180 bar 177.646188 atm
200 bar 197.3846533 atm
225 bar 222.057735 atm
250 bar 246.7308167 atm
275 bar 271.4038983 atm
300 bar 296.07698 atm
350 bar 345.4231434 atm
400 bar 394.7693067 atm
450 bar 444.11547 atm
500 bar 493.4616334 atm
600 bar 592.15396 atm
700 bar 690.8462867 atm
750 bar 740.19245 atm
800 bar 789.5386134 atm
900 bar 888.23094 atm
1000 bar 986.9232667 atm
1200 bar 1184.30792 atm
1250 bar 1233.654083 atm
1500 bar 1480.3849 atm
1750 bar 1727.115717 atm
2000 bar 1973.846533 atm
2500 bar 2467.308167 atm
3000 bar 2960.7698 atm
4000 bar 3947.693067 atm
4500 bar 4441.1547 atm
5000 bar 4934.616334 atm
6000 bar 5921.5396 atm
7000 bar 6908.462867 atm
7500 bar 7401.9245 atm
8000 bar 7895.386134 atm
9000 bar 8882.3094 atm
10000 bar 9869.232667 atm
15000 bar 14803.849 atm
20000 bar 19738.46533 atm
25000 bar 24673.08167 atm
50000 bar 49346.16334 atm
75000 bar 74019.245 atm
100000 bar 98692.32667 atm

Values based on NIST SP 811 conversion factors

Real-World Examples

Standard atmospheric pressure

1.01325 bar = 1 atm

Car tire gauge pressure

2.3 bar = 2.269923513 atm

Pressure at about 100 m underwater

10 bar = 9.869232667 atm

Full scuba tank pressure

200 bar = 197.3846533 atm

Why Convert Bars to Atmospheres?

Converting between bars (bar) and atmospheres (atm) is one of the most common pressure conversions. Whether for engineering, cooking, travel, or science, knowing how to quickly convert bar to atm saves time and prevents errors.

Pressure conversions between bar and atm are vital in automotive maintenance, meteorology, and scuba diving. Tire pressure affects fuel efficiency and safety, requiring drivers to convert between PSI and bar depending on the gauge used. Divers must strictly monitor pressure to avoid decompression sickness, often needing to convert depth and tank pressure readings. In weather forecasting, atmospheric pressure changes indicate approaching storms, with data often shared in different units globally. Failing to convert pressure accurately can lead to equipment failure, tire blowouts, or life-threatening situations underwater.

How to Convert Bars to Atmospheres

To convert bars to atmospheres, use the following formula:

atm = bar × 0.9869232667

Example: 1 bar = 0.9869232667 atm

For example, 5 bar = 4.934616334 atm, 10 bar = 9.869232667 atm, and 100 bar = 98.69232667 atm. For larger values, 1000 bar = 986.9232667 atm. Conversely, 1 atm = 1.01325 bar. Our calculator above performs this conversion instantly with full precision — no rounding errors.

Common Use Cases

  • Standard atmospheric pressure: 1.01325 bar = 1 atm
  • Car tire gauge pressure: 2.3 bar = 2.269923513 atm
  • Pressure at about 100 m underwater: 10 bar = 9.869232667 atm
  • Full scuba tank pressure: 200 bar = 197.3846533 atm

Common Mistakes to Avoid

  • Gauge vs Absolute: confusing gauge pressure (psig) with absolute pressure (psia).
  • Bar vs Pascal: 1 Bar is 100,000 Pascals, not 10 or 100.
  • Atmosphere variations: confusing standard atm with technical atm.

Pro Tips

  • Tire checks: Check tire pressure when cold (tires heat up and pressure rises while driving).
  • PSI rule: Typical car tires are 30-35 PSI.
  • Altitude effect: Air pressure drops as you go higher (ears popping).

What is a Bar?

The bar is a metric unit of pressure, exactly equal to 100,000 pascals. It is slightly less than the average atmospheric pressure at sea level.

Bars are commonly used in meteorology, scuba diving, and industry to measure fluid pressure and tire pressure (in some countries).

What is a Atmosphere?

Standard atmosphere (atm), defined as 101,325 Pascals.

Reference pressure for sea level.

Frequently Asked Questions

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