Inches of Water to Hectopascals (inH₂O → hPa)
Formula
1 inH₂O = 2.49082 hPaConversion Table
| inH₂O | hPa |
|---|---|
| 0 | 0 |
| 1.0000 | 2.4908 |
| 2.0000 | 4.9816 |
| 3.0000 | 7.4725 |
| 4.0000 | 9.9633 |
| 5.0000 | 12.454 |
| 6.0000 | 14.945 |
| 7.0000 | 17.436 |
| 8.0000 | 19.927 |
| 9.0000 | 22.417 |
| 10.000 | 24.908 |
| 11.000 | 27.399 |
| 12.000 | 29.890 |
| 13.000 | 32.381 |
| 14.000 | 34.871 |
| 15.000 | 37.362 |
| 16.000 | 39.853 |
| 17.000 | 42.344 |
| 18.000 | 44.835 |
| 19.000 | 47.326 |
| inH₂O | hPa |
|---|---|
| 20.000 | 49.816 |
| 21.000 | 52.307 |
| 22.000 | 54.798 |
| 23.000 | 57.289 |
| 24.000 | 59.780 |
| 25.000 | 62.270 |
| 26.000 | 64.761 |
| 27.000 | 67.252 |
| 28.000 | 69.743 |
| 29.000 | 72.234 |
| 30.000 | 74.725 |
| 31.000 | 77.215 |
| 32.000 | 79.706 |
| 33.000 | 82.197 |
| 34.000 | 84.688 |
| 35.000 | 87.179 |
| 36.000 | 89.670 |
| 37.000 | 92.160 |
| 38.000 | 94.651 |
| 39.000 | 97.142 |
| inH₂O | hPa |
|---|---|
| 40.000 | 99.633 |
| 41.000 | 102.12 |
| 42.000 | 104.61 |
| 43.000 | 107.11 |
| 44.000 | 109.60 |
| 45.000 | 112.09 |
| 46.000 | 114.58 |
| 47.000 | 117.07 |
| 48.000 | 119.56 |
| 49.000 | 122.05 |
| 50.000 | 124.54 |
| 51.000 | 127.03 |
| 52.000 | 129.52 |
| 53.000 | 132.01 |
| 54.000 | 134.50 |
| 55.000 | 137.00 |
| 56.000 | 139.49 |
| 57.000 | 141.98 |
| 58.000 | 144.47 |
| 59.000 | 146.96 |
| inH₂O | hPa |
|---|---|
| 60.000 | 149.45 |
| 61.000 | 151.94 |
| 62.000 | 154.43 |
| 63.000 | 156.92 |
| 64.000 | 159.41 |
| 65.000 | 161.90 |
| 66.000 | 164.39 |
| 67.000 | 166.88 |
| 68.000 | 169.38 |
| 69.000 | 171.87 |
| 70.000 | 174.36 |
| 71.000 | 176.85 |
| 72.000 | 179.34 |
| 73.000 | 181.83 |
| 74.000 | 184.32 |
| 75.000 | 186.81 |
| 76.000 | 189.30 |
| 77.000 | 191.79 |
| 78.000 | 194.28 |
| 79.000 | 196.77 |
Inches of Water to Hectopascals Conversion
Converting Inches of Water (inH₂O) to Hectopascals (hPa) is a common pressure conversion. 1 inH₂O equals 2.49082 hPa. For example, 100 inH₂O is equal to 249.082 hPa.
Quick Reference Values
1 inH₂O = 2.49082 hPa. 5 inH₂O = 12.4541 hPa. 10 inH₂O = 24.9082 hPa. 25 inH₂O = 62.2705 hPa. 50 inH₂O = 124.541 hPa. 100 inH₂O = 249.082 hPa.
What is Inches of Water?
Inches of Water (inH₂O) is a unit of pressure. Inches of water measure pressure as the height in inches of a water column. One inch of water equals 249.0889 pascals (Pa) at 4 °C. This unit is widely used to measure low-pressure differentials in HVAC and fluid systems [nist-si-guide]. The use of water columns for pressure measurement dates to early fluid mechanics studies. The inch unit was adopted in English-speaking countries for practical low-pressure measurement. It remains standardized for building and industrial applications [nist-si-guide]. Inches of water are used primarily in the United States for HVAC duct pressures, gas pressure measurements, and cleanroom environments. Other countries often use pascals or millimeters of water but recognize inH2O in specific sectors [nist-si-guide].
What is Hectopascals?
Hectopascals (hPa) is a unit of pressure. The hectopascal is a unit of pressure equal to 100 pascals. It is defined as exactly 100 newtons per square meter (100 N/m²), where the pascal (Pa) is the SI derived unit of pressure. The hectopascal is widely used in meteorology for atmospheric pressure measurements and aligns with the SI system as per international standards [bipm-si-brochure]. The pascal unit was named after Blaise Pascal and officially adopted by the General Conference on Weights and Measures (CGPM) in 1971. The hectopascal emerged as a convenient multiple used in meteorology to represent atmospheric pressure values in the 20th century [cgpm-resolutions]. Hectopascals are standard in weather reports worldwide, especially in Europe, Asia, and Australia. The US National Weather Service uses millibars, numerically equivalent to hectopascals, for atmospheric pressure. It is recognized by ISO 80000 as a unit of pressure [iso-80000].
Common Misspellings
People often search for this conversion using these alternate spellings: inch of water, inch-water, in h2o, inch h20, hecto pascals, hecto-pascals, hecto pascal, hec topascal. All of these refer to the Inches of Water to Hectopascals conversion.