To convert kilopounds per square inch to feet of water, multiply by 2306.658741. That factor is the whole relationship: both units measure pressure, so the conversion is a proportion with no offset and no substance-specific constant.
Pump head expressed as a column of water — the way pump curves are drawn. One thousand psi; the unit US steel and alloy strengths are quoted in.
Gauge versus absolute. A tyre gauge reading 32 psi means 32 psi above atmospheric, which is about 46.7 psi absolute. Converting the number is straightforward; remembering which zero it was measured from is where the mistakes happen. N/mm² and MPa are the same size, so a drawing quoting either is quoting the same stress. Two tables follow: rounded steps for quick lookup, and a set of real reference quantities converted into feet of water, which is usually more useful than the bare number.
The formula
kilopounds per square inch- The amount you are converting, in kilopounds per square inch
2306.65874128- The exact number of feet of water in one kilopound per square inch
feet of water- The converted result
How it works, step by step
- Enter the value in kilopounds per square inch.
- It is multiplied by 2306.65874128, the exact factor between the two units.
- The answer is shown in feet of water, with the reverse conversion beneath it.
- Check the reference table if you want a figure of comparable size.
Worked examples
Blood pressure, systolic: 0.00232 ksi in feet of water
Take blood pressure, systolic, roughly 0.00232 ksi. The conversion is a single multiplication — 0.00232 × 2306.66 — giving 5.35145 ftH₂O. Because the relationship is proportional, doubling the input doubles the answer to 10.7029 ftH₂O.
Sea-level air: 0.0147 ksi in feet of water
At 0.0147 ksi (sea-level air), the same quantity in feet of water is 0.0147 × 2306.66 = 33.9079 ftH₂O. One kilopound per square inch is 2306.66 feet of water, so the numbers grow as expected.
How to read your score
Frequently asked questions
How many feet of water are in one kilopound per square inch?
Exactly 2306.65874128. Every figure on this page is that one number multiplied by your input, so the only rounding is at the display step.
What is the formula to convert kilopounds per square inch to feet of water?
feet of water = kilopounds per square inch × 2306.65874128. Reversed, kilopounds per square inch = feet of water ÷ 2306.65874128, which is the same as multiplying by 0.0004335275011.
Which is the bigger unit, the kilopound per square inch or the foot of water?
The kilopound per square inch. One kilopound per square inch equals 2306.66 feet of water.
What does this quantity actually measure?
Both units measure pressure. That is why a single factor is enough: there is no temperature offset and no material property involved, unlike conversions that cross between different quantities.
What is a kilopound per square inch?
One thousand psi; the unit US steel and alloy strengths are quoted in.
What is a foot of water?
Pump head expressed as a column of water — the way pump curves are drawn.
Why does my answer differ from another converter?
Almost always because the other tool rounded the factor before multiplying. This page keeps full double precision through the calculation and rounds only for display, and it prints the factor it used so you can see where any difference came from.
Is there a quick way to do ksi to ftH₂O in my head?
Plenty of people do this in their head: multiply by 2300 instead of using the exact factor 2306.658741. At 100 that shortcut gives 230,000 feet of water, off by 665.9 feet of water or about 0.29%. Fine for a rough estimate, not fine for anything you are cutting to size or dosing.
Kilopounds Per Square Inch to feet of water reference tables
| Kilopounds Per Square Inch | Feet Of Water |
|---|---|
| 0.5 ksi | 1153.33 ftH₂O |
| 1 ksi | 2306.66 ftH₂O |
| 2 ksi | 4613.32 ftH₂O |
| 3 ksi | 6919.98 ftH₂O |
| 5 ksi | 11,533.3 ftH₂O |
| 10 ksi | 23,066.6 ftH₂O |
| 20 ksi | 46,133.2 ftH₂O |
| 25 ksi | 57,666.5 ftH₂O |
| 50 ksi | 115,333 ftH₂O |
| 75 ksi | 172,999 ftH₂O |
| 100 ksi | 230,666 ftH₂O |
| 250 ksi | 576,665 ftH₂O |
| 500 ksi | 1.15333e+06 ftH₂O |
| 1000 ksi | 2.30666e+06 ftH₂O |
| 5000 ksi | 1.15333e+07 ftH₂O |
Exact factor: 1 kilopound per square inch = 2306.65874128 feet of water.
| Quantity | ksi | ftH₂O |
|---|---|---|
| Sea-level air | 0.0147 ksi | 33.9 ftH₂O |
| A car tyre | 0.032 ksi | 73.81 ftH₂O |
| Blood pressure, systolic | 0.00232 ksi | 5.352 ftH₂O |
| A bicycle tyre | 0.09 ksi | 207.6 ftH₂O |
| A domestic water main | 0.05802 ksi | 133.8 ftH₂O |
| A steam boiler | 0.145 ksi | 334.6 ftH₂O |
Published reference values, converted with the same factor this page uses.