Pressure

Inches of Water to Bar

Convert inches of water to bar instantly. 1 inH2O = 0.002490889 bar. Includes the exact factor, a conversion table of common values and the definition of both units.

inH2O
Bar
One step, one exact factorInches of Waterwhat you have× 0.002490889Barwhat you getBoth units are defined against the same base unit, so the factor is exact — never an approximation.

How to convert inches of water to bar

To convert inches of water to bar, divide by 401.4630920928 (multiply by 0.002490889). The relationship is fixed, so the same factor works for any quantity — there is nothing to look up and nothing that changes with temperature, location or context.

bar = inH2O × 0.002490889

Inches of Water to Bar conversion table

The values people look up most often, rounded for reading. Use the calculator above for anything in between.

Inches of WaterBar
1 inH2O0.002491 bar
2 inH2O0.004982 bar
3 inH2O0.007473 bar
5 inH2O0.012454 bar
10 inH2O0.024909 bar
20 inH2O0.049818 bar
25 inH2O0.062272 bar
50 inH2O0.124544 bar
100 inH2O0.249089 bar
500 inH2O1.245445 bar
1,000 inH2O2.490889 bar

What is a inches of water?

A low-pressure unit used for ventilation and gas appliances.

What is a bar?

Defined as exactly 100 kPa, very close to one atmosphere at sea level.

The formula

bar = inH2O × 0.002490889

Every result on this page comes from this formula. Nothing is rounded until the final display, so figures match a spreadsheet to the cent.

How to use the Inches of Water to Bar

  1. Type the number of inches of water you want to convert.
  2. Read the result in bar straight away — there is no button to press.
  3. Check the table below for the values that come up most often, or reverse the conversion with the linked bar to inches of water page.

Inches of Water to Bar — frequently asked questions

How many bar are in a inches of water?

One inches of water equals 0.002490889 bar. bar = inH2O × 0.002490889

What is the formula to convert inches of water to bar?

The formula is bar = inH2O × 0.002490889. It is an exact definition rather than an approximation, so the conversion never drifts no matter how large the number.

How do I convert bar back to inches of water?

Divide instead of multiplying: one bar is 401.4630920928 inH2O. The reverse converter is linked in the related tools list.

Is this conversion exact?

Yes. Both units are defined against the same base unit by international agreement, so the factor is exact — any rounding you see is only in the display, which you can widen by entering more decimal places.

Is this inches of water to bar free to use?

Yes. Every calculator on the site is free, needs no sign-up, and runs entirely in your browser, so your figures never leave your device.

What people search for

This page answers each of these searches. They are the exact phrases visitors use to find the inches of water to bar.

  • inches of water to bar
  • 1 inches of water to bar
  • how many bar in a inches of water
  • inh2o2bar
  • inches of water in bar
  • inches of water to bar converter
  • convert inches of water to bar

About this calculator

Written and reviewed by The Samsung Calculator editorial team. Every calculator is written against a published formula, reviewed against at least one independent reference implementation, and dated when it changes.

Last reviewed August 19, 2026 · Calculation runs client-side · No data collected · Report an error