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IPC Ch.6
Validated against the standard.
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How it works
Enter your values
Type in your inputs — the app fills code tables and constants for you, so there's nothing to look up.
Get a code-checked result
Instant answer with a clear PASS / FAIL and the exact IPC Ch.6 reference behind every number.
Save & export
Keep a history of calculations and export a clean PDF report to share or attach to a permit (Pro).
What this calculator does
Head loss is the pressure a system gives up to friction as water moves through pipe and fittings. This app computes friction loss with the Hazen-Williams equation so you can confirm the most remote fixture still has enough residual pressure, or size a pump.
What it accounts for
- Flow rate (GPM) and pipe size.
- Pipe material through its C-factor (smoother pipe = higher C = less loss).
- Developed length plus the equivalent length of fittings and valves.
- Elevation change, since every foot of lift costs about 0.433 psi.
Worked example
15 GPM through 100 ft of 3/4-inch copper loses on the order of 8–10 psi to friction; add elevation (10 ft of lift ≈ 4.3 psi) and you can check what pressure remains at the fixture.
Related calculators
Use it with the water pipe sizing calculator and the pipe offset calculator.
Head loss FAQ
What equation does it use?
The Hazen-Williams equation, the standard for water in pressurized pipe, using a roughness C-factor that depends on the pipe material.
Does it include fittings?
Yes. Fittings and valves are added as equivalent length of straight pipe, so the total developed length reflects the real path.
How is elevation handled?
Each foot of vertical lift adds about 0.433 psi of static head, which the app adds to or subtracts from the friction loss.
Does it work offline?
Yes, it runs 100% offline with no account. Free with rewarded ads; a one-time $2.99 Pro unlock adds PDF export and saved history.
Get Head Loss Calculator on your phone
Free with rewarded ads · $2.99 lifetime Pro · iOS & Android. Works 100% offline on the job site.