Convert kPa to psi

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Enter a pressure in kilopascals and read the result in psi. One kilopascal is 0.145 psi, so 240 kPa comes to 34.81 psi. The tables give 76 ready conversions, the pressures at which the tire pressure warning light comes on, and MAP sensor readings turned into gauge pressure.

kPa
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What is a kilopascal, and what is psi?

A kilopascal is a thousand pascals. The pascal is the SI unit of pressure and equals a force of one newton acting on one square meter[1]. The General Conference on Weights and Measures adopted the name pascal for this unit in 1971[2].


The standard atmosphere, which the same conference defined in a 1954 resolution, is exactly 101.325 kPa[3].


Psi stands for pound-force per square inch, the pressure produced when a force of one pound-force acts on an area of one square inch[4]. One inch is exactly 2.54 cm[5], and other lengths in inches convert in the inches to cm converter. The conversion table of NIST, the US national metrology institute, gives one psi as 6.894757 kPa[5].


One hundred kilopascals is exactly one bar[5]. A value written in bar converts to psi in the bar to psi converter.

Tire valve with a black and white cap on an alloy car wheel
The valve on a passenger car wheel, used to check and top up tire pressure. Photo: Erik Mclean, Unsplash.

How many psi is one kilopascal?

One kilopascal is 0.145038 psi. To convert kilopascals to psi, divide the number of kilopascals by 6.894757, the value of one psi in the NIST conversion table[5].


A pressure of 220 kPa gives 31.91 psi. A pressure of 240 kPa is 34.81 psi. A pressure of 250 kPa equals 36.26 psi. Multiplying 34.81 psi back by the same number gives 240.01 kPa, the starting value to within rounding.


The converter does this division as you type and shows the result to hundredths of a psi. The field also accepts decimals, so 232.5 kPa becomes 33.72 psi. With smaller values the result has more decimal places, so half a kilopascal shows as 0.07252 psi.


The conversion keeps the type of pressure. Gauge pressure read from a gauge stays gauge pressure in psi. A reading from a sensor that measures from vacuum stays absolute pressure, and the MAP sensor table gives the matching gauge pressure.

How do you convert kPa to psi? Formula and example

Formula: psi = kPa ÷ 6.894757


Take 230 kPa. Dividing by 6.894757 gives 33.36 psi. Multiplying by 0.145038 gives the same result, because that number is the reciprocal of the divisor.


The converter also accepts negative values. A vacuum gauge shows pressure below atmospheric with a minus sign, because it takes the ambient pressure as its zero[6]. Enter -30 kPa and the result field shows -4.351 psi.


For the other direction, from psi to kilopascals, use the psi to kPa converter.

How many psi is a given number of kilopascals?

The rows cover pressures from 1 to 10,000 kPa. Each result has as many decimal places as the converter shows: two, and for values below ten psi enough to keep four significant digits.
KilopascalsPsi
1 kPa0.145 psi
2 kPa0.2901 psi
3 kPa0.4351 psi
5 kPa0.7252 psi
7 kPa1.015 psi
10 kPa1.45 psi
15 kPa2.176 psi
20 kPa2.901 psi
25 kPa3.626 psi
30 kPa4.351 psi
35 kPa5.076 psi
40 kPa5.802 psi
50 kPa7.252 psi
60 kPa8.702 psi
69 kPa10.01 psi
70 kPa10.15 psi
75 kPa10.88 psi
80 kPa11.6 psi
88 kPa12.76 psi
90 kPa13.05 psi
95 kPa13.78 psi
100 kPa14.5 psi
101.325 kPa14.7 psi
105 kPa15.23 psi
108 kPa15.66 psi
110 kPa15.95 psi
120 kPa17.4 psi
125 kPa18.13 psi
130 kPa18.85 psi
137 kPa19.87 psi
140 kPa20.31 psi
150 kPa21.76 psi
160 kPa23.21 psi
170 kPa24.66 psi
175 kPa25.38 psi
180 kPa26.11 psi
190 kPa27.56 psi
200 kPa29.01 psi
205 kPa29.73 psi
210 kPa30.46 psi
215 kPa31.18 psi
220 kPa31.91 psi
225 kPa32.63 psi
230 kPa33.36 psi
235 kPa34.08 psi
240 kPa34.81 psi
245 kPa35.53 psi
250 kPa36.26 psi
255 kPa36.98 psi
260 kPa37.71 psi
270 kPa39.16 psi
275 kPa39.89 psi
280 kPa40.61 psi
290 kPa42.06 psi
300 kPa43.51 psi
310 kPa44.96 psi
320 kPa46.41 psi
340 kPa49.31 psi
350 kPa50.76 psi
360 kPa52.21 psi
380 kPa55.11 psi
400 kPa58.02 psi
420 kPa60.92 psi
450 kPa65.27 psi
500 kPa72.52 psi
550 kPa79.77 psi
600 kPa87.02 psi
650 kPa94.27 psi
700 kPa101.53 psi
800 kPa116.03 psi
900 kPa130.53 psi
1,000 kPa145.04 psi
1,500 kPa217.56 psi
2,000 kPa290.08 psi
4,000 kPa580.15 psi
10,000 kPa1,450.38 psi
The 101.325 kPa row is the standard atmosphere. In psi it gives 14.7, or 14.69595 psi to five decimal places.

At what pressure does the tire pressure warning light come on?

In the European Union, Regulation (EC) No 661/2009 required a tire pressure monitoring system, TPMS for short, on all new passenger cars from November 1, 2014[7]. UN Regulation No. 141 sets out when such a system must switch on the warning light. That happens when the in-service operating pressure in a tire has dropped by 20 percent or is at a minimum of 150 kPa, whichever is higher[8].
Operating pressurePsiWarning at (kPa)Warning at (psi)
180 kPa26.11 psi150 kPa21.76 psi
190 kPa27.56 psi152 kPa22.05 psi
200 kPa29.01 psi160 kPa23.21 psi
210 kPa30.46 psi168 kPa24.37 psi
220 kPa31.91 psi176 kPa25.53 psi
230 kPa33.36 psi184 kPa26.69 psi
240 kPa34.81 psi192 kPa27.85 psi
250 kPa36.26 psi200 kPa29.01 psi
260 kPa37.71 psi208 kPa30.17 psi
270 kPa39.16 psi216 kPa31.33 psi
280 kPa40.61 psi224 kPa32.49 psi
290 kPa42.06 psi232 kPa33.65 psi
300 kPa43.51 psi240 kPa34.81 psi
320 kPa46.41 psi256 kPa37.13 psi
350 kPa50.76 psi280 kPa40.61 psi
Example from the table: at an operating pressure of 240 kPa the warning light must come on once the pressure falls to 192 kPa, which is 27.85 psi. At 180 kPa a 20 percent drop would give 144 kPa. That value is below the minimum, so the threshold is 150 kPa.

How much gauge pressure in psi does a MAP sensor reading give?

A manifold absolute pressure sensor, MAP for short, measures absolute pressure, counted from vacuum. Under the same conditions a boost sensor reads about 100 kPa lower, because it measures pressure above a set reference pressure[9]. To compare the two readings, the table subtracts the standard atmosphere of 101.325 kPa[3] from the sensor value and divides the difference by 6.894757.
MAP sensor readingGauge pressure
20 kPa-11.8 psi
30 kPa-10.34 psi
40 kPa-8.894 psi
50 kPa-7.444 psi
60 kPa-5.994 psi
70 kPa-4.543 psi
80 kPa-3.093 psi
90 kPa-1.643 psi
100 kPa-0.1922 psi
101.325 kPa0 psi
108 kPa0.9681 psi
110 kPa1.258 psi
120 kPa2.709 psi
130 kPa4.159 psi
140 kPa5.609 psi
150 kPa7.06 psi
160 kPa8.51 psi
170 kPa9.96 psi
180 kPa11.41 psi
200 kPa14.31 psi
220 kPa17.21 psi
250 kPa21.56 psi
300 kPa28.82 psi
Negative values mean vacuum in the manifold. Zero corresponds to a reading of 101.325 kPa. A reading of 108 kPa gives 0.9681 psi of gauge pressure. Actual air pressure varies with altitude and weather[6], so on a given day the zero point can be a few kilopascals higher or lower.

How much psi does an electric pressure cooker reach?

The UK user manual of the Instant Pot Duo gives the cooking pressure in both units. Low pressure is 35–55 kPa and high pressure is 65–85 kPa, which the same page puts at 5–8 psi and 9.4–12.3 psi[10].


The converter agrees with that page: 35 kPa is 5.076 psi, 55 kPa is 7.977 psi, 65 kPa is 9.427 psi and 85 kPa is 12.33 psi. The cooking table in the same manual prints 10.2–11.6 psi next to 65–85 kPa. Those psi figures match only 70.33–79.98 kPa, the middle part of the kilopascal range.

Which number formats does this converter accept?

The table shows what the field does with the ways a pressure usually reaches it from stickers, manuals and spreadsheets. The converter itself calculated every result.
What you typeWhat the converter showsNote
24034.81 psiA plain number is read as kilopascals, because that’s what the field is labeled.
240 kPa34.81 psiThe kPa symbol pasted along with the number is skipped, so only the number counts.
2.4 bar34.81 psiA pressure in bar is turned into kilopascals by the field itself, so the result matches 240 kPa.
35 psi35 psiA value typed straight in psi is recognized by its symbol and left as it is.
101.32514.7 psiThat’s the standard atmosphere in kilopascals, and that’s how we read it. A note under the field says: Read as 101.325. If you meant 101325, type 101325.
2.50.3626 psiThe period is your decimal point, and that’s exactly how we read it.
2,50.3626 psiA comma with fewer than three digits after it is a decimal comma from a European document, so we read two and a half kilopascals.
1.5000.2176 psiA single period is always read as a decimal point, so the field takes one and a half kilopascals. A note under the field says: Read as 1.5. If you meant 1500, type 1500.
1,500217.56 psiA comma followed by three digits groups thousands, so the field reads fifteen hundred kilopascals. A note under the field says: Read as 1500. If you meant 1.5, type 1.5.
1/20.07252 psiA fraction with a slash is worked out for you, so half a kilopascal doesn’t need to become 0.5 first.
-80-11.6 psiA minus sign is accepted, so a vacuum gauge reading converts too.
- 80 kPaThe result field stays empty.A minus separated by a space isn’t joined to the number, so nothing is calculated. Type the minus right before the digit.

Convert other units to Pounds per square inch (psi)

atm to psibar to psi

Convert Kilopascals (kPa) to other units

kPa to bar

Sources

  1. SI: A concise summary of the International System of Units — Bureau International des Poids et Mesures
  2. Decision of the 14th CGPM (1971): pascal and siemens — Bureau International des Poids et Mesures
  3. Resolution 4 of the 10th CGPM (1954): Definition of the standard atmosphere — Bureau International des Poids et Mesures
  4. Pound per square inch — Wikipedia
  5. NIST Guide to the SI, Appendix B.9: Factors for units listed by kind of quantity or field of science — National Institute of Standards and Technology
  6. Pressure measurement — Wikipedia
  7. Regulation (EC) No 661/2009 of the European Parliament and of the Council of 13 July 2009 — EUR-Lex
  8. UN Regulation No 141 — Uniform provisions concerning the approval of vehicles with regard to their Tyre Pressure Monitoring Systems (TPMS) — EUR-Lex
  9. MAP sensor — Wikipedia
  10. Duo Multi-Use Pressure Cooker: User manual — Instant Pot
  11. CONVERT function — Microsoft
  12. Pascal (unit) — Wikipedia

Every figure in the tables was computed from the unit definitions and checked arithmetically before publication. Historical values and the names of local units come from the sources listed above.

Content last reviewed: · written and checked by the Arteon team

Common questions about converting kPa to psi

How many bar is 240 kPa?

240 kPa is 2.4 bar, because one bar is exactly 100 kPa[5]. In psi the same value is 34.81. When a gauge shows psi and you need bar, the psi to bar converter gives the result.

Is tire pressure in kPa given as gauge pressure?

Yes. Tire pressure is given as gauge pressure by convention, meaning the pressure above ambient[6]. You convert a value in kilopascals directly, and the result in psi is gauge pressure as well.

How do you read vacuum from a MAP sensor in psi?

Subtract 101.325 kPa, the standard atmosphere, from the reading and divide the result by 6.894757. A MAP sensor measures absolute pressure and never displays a negative reading[9], so the minus sign only appears after this subtraction. A reading of 65 kPa gives -5.268 psi this way.

How do you convert kPa to psi in your head?

Multiply the number of kilopascals by 0.145. The result comes out less than three hundredths of a percent below the exact value. For 1,000 kPa the mental calculation gives 145 psi, and the converter shows 145.04 psi.

How do you convert kPa to psi in Excel?

Use the CONVERT function: =CONVERT(A1,"kPa","psi"). Unit codes are case-sensitive, and the prefix k can be added to any metric unit, including the pascal code Pa[11].

What is the symbol for kilopascal?

kPa. The kilo prefix has the lowercase symbol k[1]. The pascal symbol starts with a capital letter, because symbols of units named after a person are written that way[1], and the pascal is named after Blaise Pascal[12].

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