PSI to inH2O Converter
Pressure · unit-converter
Convert PSI to inH2O with a fixed input and output unit, step-by-step formula line, and reference tables. All calculations bridge through pascal with fixed definitions (standard atmosphere = 101,325 Pa; torr and mmHg = atm/760; plus industrial/manometer units like kgf/cm², inHg, inH2O, and mmH2O).
About PSI
Pounds-force per square inch (PSI) is common for tires, hydraulics, and US industrial equipment.
About inH2O
Inches of water column (inH2O) is common in low-pressure HVAC and duct static-pressure measurements.
How to convert psi to inch of water (inh2o, 4 °c)
1 psi equals 27.67990471020167 inh2o in this tool (via pascal):
1 psi = (6894.757293168 Pa ÷ 249.08891 Pa) inh2o = 27.67990471020167 inh2o
Each psi carries 6894.757293168 Pa and each inh2o 249.08891 Pa, so one psi equals 6894.757293168 ÷ 249.08891 inh2o.
Let p(psi) be pressure in PSI (psi), and p(inh2o) in inH2O (inh2o). Then:
p(inh2o) = p(psi) × (6894.757293168 / 249.08891)
Equivalently, divide by how many psi fit into one inh2o (Pa per inh2o divided by Pa per psi):
p(inh2o) = p(psi) ÷ 0.03612729200008558
Examples
Example #1: Convert 1 psi to inh2o
1 psi = 1 psi × (6894.757293168/249.08891) inh2o = 27.6799047102 inh2o
1 psi = 1 psi ÷ 0.03612729200008558 = 27.6799047102 inh2o
1 psi × (6,894.757293168/249.08891) = 27.679905 inh2o
Example #2: Convert 10 psi to inh2o
10 psi = 10 psi × (6894.757293168/249.08891) inh2o = 276.799047102 inh2o
10 psi = 10 psi ÷ 0.03612729200008558 = 276.799047102 inh2o
10 psi × (6,894.757293168/249.08891) = 276.799047 inh2o
Summary
To convert PSI to inH2O, multiply the value in psi by (6894.757293168 Pa per psi) / (249.08891 Pa per inh2o). Equivalently: value_inh2o = value_psi × (6894.757293168 / 249.08891). Numerically, 1 psi equals 27.67990471020167 inh2o.
Relationship context
Both PSI and inH2O are converted by fixed multiples of the pascal. Multiplying by (Pa per psi) ÷ (Pa per inh2o) gives the same result as passing through pascal, keeping bar, atm, PSI, kPa, hPa, torr, and mmHg consistent on the hub.
Conversion tables
| PSI (psi) | inH2O (inh2o) |
|---|---|
| 0.1 | 2.767990471 |
| 1 | 27.6799047102 |
| 2 | 55.3598094204 |
| 3 | 83.0397141306 |
| 4 | 110.719618841 |
| 5 | 138.399523551 |
| 6 | 166.079428261 |
| 7 | 193.759332971 |
| 8 | 221.439237682 |
| 9 | 249.119142392 |
| PSI (psi) | inH2O (inh2o) |
|---|---|
| 10 | 276.799047102 |
| 20 | 553.598094204 |
| 30 | 830.397141306 |
| 40 | 1,107.19618841 |
| 50 | 1,383.99523551 |
| 60 | 1,660.79428261 |
| 70 | 1,937.59332971 |
| 80 | 2,214.39237682 |
| 90 | 2,491.19142392 |
| 100 | 2,767.99047102 |