Pipe volume, flow velocity, Hazen-Williams pressure loss, pipe sizing by velocity, thermal expansion, drain slope, tank fill time and bucket flow tests.
payments ON MAINNET (real money) · 8 live endpoints
| Endpoint | Price | What it answers |
|---|---|---|
GET /bucket-test | $0.02 | Flow rate in gpm and litres per minute from a bucket test: container volume and seconds to fill, with a daily-use estimate. |
GET /drain-slope | $0.02 | Fall needed for a drain run at a given slope in inches per foot, or the slope of a measured fall, with typical code minimums. |
GET /flow-velocity | $0.02 | Water velocity in feet per second from flow in gpm and pipe size, or the flow a pipe carries at a chosen velocity. |
GET /pipe-size | $0.02 | Smallest standard copper Type L or PVC Schedule 40 pipe that keeps water under a maximum velocity at your flow rate. |
GET /pipe-volume | $0.02 | Water held in a run of pipe in gallons and litres per foot and in total, from nominal size or inside diameter. |
GET /pressure-loss | $0.02 | Friction pressure loss in psi (and feet of head) over a pipe run by the Hazen-Williams formula, from flow, size and C factor. |
GET /tank-fill-time | $0.02 | Time to fill or drain a tank from its volume or round tank size and flow in gpm, with an optional outflow. |
GET /thermal-expansion | $0.02 | How much a pipe run lengthens or shortens with temperature for copper, steel, PVC, CPVC, PEX or ABS, in inches and mm. |
GET /catalog returns this list as JSON. Activity hub · uptime.
Plumbing arithmetic computed locally from the numbers given, using standard hydraulic formulas and published pipe dimensions, provided as is. These are planning estimates: real systems also have fittings, valves, elevation, water temperature and local plumbing codes that govern what is permitted. Not a code-compliance check and not a substitute for a licensed plumber or engineer. Every paid response carries a disclaimer field.