PEX tubing calculator
Eight points of use with an average 25 ft run, each fed by a hot and a cold line, need 400 ft of PEX plus 10% waste: 440 ft in all. Add the coil length and you also see how many whole coils to buy. Free in your browser.
- Free
- Runs in your browser
- No sign-up
- Your data stays on your device
Run — free
Worked example
- Fixtures
- 8
- Avg run per fixture
- 25
- Waste percent
- 10 ft
- Lines
- 2
- Single line length
- 200
- Net length
- 400
Planning a PEX repipe or a new manifold layout means knowing how much tubing to buy before you open coils on site. Optional coil length packs the purchase quantity into whole stock rolls so shopping lists match what suppliers sell. Use it for early budgets; refine with a room-by-room measure when drawings are final.
Counting tubing from outlets instead of drawings
A PEX system usually starts at a central manifold or a main trunk and sends a run to each point of use: sinks, toilets, showers, dishwashers. Instead of measuring every run on a plan, the calculator multiplies the number of those outlets by the average one-way distance from the manifold to each one, then by the number of lines each needs. Eight outlets at 25 ft make 200 ft of single line; with hot and cold that becomes 400 ft. A waste allowance, 10% by default, is then added to that net length, giving 440 ft. Typical homes land somewhere between 15 and 40 ft per outlet, depending on the layout.
Turning the estimate into an order
The unit you pick is only a label: the calculator does not convert feet to metres, so keep every length in the same system. If you add the length of the coils your supplier sells, the total is rounded up to whole coils, so the shopping list matches what is on the shelf. Treat the result as an early budget figure for a repipe or a new manifold layout. When the drawings are final, refine it with a room-by-room measure, and before ordering a large job, check local code, the manufacturer's expansion guidance and a final walk-through.
How outlets and run length add up to total tubing
Cross-linked polyethylene (PEX) plumbing is usually laid out from a central manifold or from a main trunk with home-run or hybrid branches. The default line count is two, covering a conventional hot-plus-cold pair; set lines to one for cold-only branches, recirculation stubs, or dedicated appliance feeds, or raise it for multi-zone specialty layouts up to four. Waste percent then adds a fraction of that net length—ten percent by default—so you are not short when a run snakes through joists or a cut is wasted at a fitting.
Total length is net plus waste. When you also supply a coil or stick length (for example one hundred feet), the service ceilings total length over that stock size to report how many coils to buy and the purchased length at whole-coil increments.
What you can do with it
SEO widgets and DIY planning
Embed the free browser path on a PEX tubing calculator page so visitors get net, waste, and total length without leaving the article.
FAQ
Does the calculator convert feet to meters?
No. unit is a label (ft or m).
How much PEX do I need for 8 sinks, toilets and showers?
With an average run of 25 ft and two lines to each one for hot and cold, you need 400 ft of tubing. Adding the default 10% waste brings the order to 440 ft.
Why are two lines counted for each sink or shower?
Most points of use take a hot and a cold line, so two is the starting point. Use one for cold-only branches, recirculation stubs or a dedicated appliance feed, and up to four for specialty multi-zone layouts.
How much waste should I add to a PEX estimate?
Ten percent is the default, and you can choose anything from 0 to 50. The allowance covers scrap, runs that snake around joists and obstacles, and tubing lost at fittings, and it is added after the lines are counted.
How do I work out how many coils of PEX to buy?
Enter the length of the coils or sticks your supplier sells, such as 100 ft. The total is divided by that length and rounded up, so you also see the length you will actually buy in whole coils.
Related tools
For developers — API access
Everything on this page is available programmatically. This section is for teams who want to wire it into their own systems; everyone else can just use the tool above.
API endpoint
Prefer to automate it? One authenticated POST creates the task; the result comes back by webhook or a signed link. The same capability also runs here on the web, by email and from Telegram — and soon from our app too.
Call it from your stack
curl -X POST https://api.kit.forhosting.com/home/pex-tubing \
-H "Authorization: Bearer $KIT_KEY" \
-H "Content-Type: application/json" \
-d '{"fixtures":8,"avg_run_per_fixture":25}'const res = await fetch("https://api.kit.forhosting.com/home/pex-tubing", {
method: "POST",
headers: {
"Authorization": `Bearer ${process.env.KIT_KEY}`,
"Content-Type": "application/json"
},
body: JSON.stringify({
"fixtures": 8,
"avg_run_per_fixture": 25
})
});
const { task_id } = await res.json();import os, requests
res = requests.post(
"https://api.kit.forhosting.com/home/pex-tubing",
headers={"Authorization": f"Bearer {os.environ['KIT_KEY']}"},
json={
"fixtures": 8,
"avg_run_per_fixture": 25
},
)
task_id = res.json()["task_id"]<?php
$res = file_get_contents("https://api.kit.forhosting.com/home/pex-tubing", false, stream_context_create([
"http" => [
"method" => "POST",
"header" => "Authorization: Bearer " . getenv("KIT_KEY") . "\r\nContent-Type: application/json",
"content" => '{"fixtures":8,"avg_run_per_fixture":25}',
],
]));
$task = json_decode($res, true);body := bytes.NewBufferString(`{"fixtures":8,"avg_run_per_fixture":25}`)
req, _ := http.NewRequest("POST", "https://api.kit.forhosting.com/home/pex-tubing", body)
req.Header.Set("Authorization", "Bearer "+os.Getenv("KIT_KEY"))
req.Header.Set("Content-Type", "application/json")
res, _ := http.DefaultClient.Do(req)Example request
{
"fixtures": 8,
"avg_run_per_fixture": 25
}Example response
{
"task_id": "tsk_a1b2c3d4e5f6a1b2c3d4e5f6",
"type": "home.pex_tubing",
"status": "queued",
"_links": {
"result": "/tasks/tsk_…/result"
}
}The API is asynchronous: the call returns a task_id immediately and the result arrives by webhook. Polling is capped at 1 req/s per task.
Pricing
Published price — no tokens, no invented credits. A failed task is never charged.
Errors
| HTTP | Code | Meaning |
|---|---|---|
401 | unauthorized | Missing or invalid API key. |
402 | insufficient_balance | Your balance doesn't cover the task price. |
404 | unknown_type | That task type doesn't exist. |
429 | rate_limited | Too many requests. Use the webhook instead of polling. |
Technical notes
Input fields, units, defaults, and response shape
Unit is a label only—the calculator does not convert feet to meters—so keep every length field in the same system. Optionally send waste_percent between zero and fifty (default ten), lines as a whole number from one to four (default two for hot and cold), coil_length as a positive stock length when you want coil packing, and unit as ft or m (default ft). Aliases such as fixture_count, avg_run, waste, supply_lines, and roll_length are accepted so forms and spreadsheets can map without renaming every column. Pair the estimate with local code, manufacturer expansion guidance, and a final walk-through measure before ordering large jobs: this endpoint is a transparent takeoff aid, not a stamped plumbing design.
Where a PEX tubing length API earns its keep
Home-improvement sites and SEO landings that rank for PEX tubing calculator need a live tool whose free browser path matches the paid automation path on the same pure module. Failed validation does not consume balance. Plumbing estimators embed the call in quote forms so customers see total footage and coil counts next to manifold and fitting line items before a site visit.
Integration use cases
Residential repipe material takeoffs
Enter fixture count and average manifold run to estimate total PEX footage and optional coil count before ordering stock for a whole-house repipe.
Contractor quote and lead forms
POST fixtures, avg_run_per_fixture, and waste_percent from a web form so quotes show the same total_length your field sheet will use later.
Technical questions
How does the PEX tubing calculator estimate total length?
It multiplies fixtures by avg_run_per_fixture by lines (default 2 for hot+cold), then adds waste_percent of that net length. Optional coil_length yields coils_needed = ceil(total_length / coil_length).
What is the default waste percent?
Ten percent. You can set waste_percent from 0 to 50 to match how much scrap and routing allowance your crew expects.
Why is lines defaulted to 2?
Most fixtures need both hot and cold supply. Use lines=1 for cold-only or single dedicated runs; use 3–4 only for specialty multi-line layouts.
What does the PEX tubing calculator cost?
The browser tool is free. API requests use prepaid KIT balance at $0.002 per successful call; invalid input is not billed.