About

About FitUp and the person who makes it

FitUp is a pipe offset calculator app for iPhone. It works out the travel, the run, the take-outs, the weld gaps, and the cut length for simple and rolling pipe offsets, and saves each answer to a job's cut list.

FitUp at a glance

What it is: A layout calculator for pipe offsets: simple offset, rolling offset, a take-out chart, and jobs with cut lists.
Who it is for: Pipefitters, pipe welders, steamfitters, HVAC techs, plumbers, and apprentices learning the math.
Platform: iPhone, iOS 17 or later. App Store category: Utilities. No Android version.
Price: Free to download, with unlimited 45 degree offsets. Optional Pro subscription: $4.99 a month, or $29.99 a year after a 7-day free trial. See pricing.
Developer: Michael Alcalde, an independent iOS developer, who sells FitUp on the App Store.
Contact: jayalcalde93@gmail.com, or the support page.

Why it exists

Most offsets on a job still get worked out on a piece of cardboard: offset times 1.414, minus two take-outs, minus two gaps, then a decimal turned into a mark on the tape. The steps are simple; doing them the same way every time, tired, in a mechanical room, is not. FitUp does those steps in a fixed order, shows every one, and answers in the number you mark on the pipe.

The name comes from the trade. Fit-up is the pipefitter's word for lining up pipe and fittings before the weld, the moment a wrong cut shows.

How the math is checked

Every number in the app comes from one small set of formulas, computed in full and rounded once for display. The app's code includes a self-test that checks the travel and run multipliers for the five standard angles (1.414 and 1.000 at 45, 2.000 and 1.732 at 30, 1.155 and 0.577 at 60, 2.613 and 2.414 at 22.5, 5.126 and 5.027 at 11.25), worked examples such as a 10 inch offset on 2 inch pipe cutting at 11 1/8, and the shortest offset that fits on each pipe size. The web calculators on this site are a port of the same code and are tested against the same cases.

Take-outs ship as commonly published butt-weld values and are labeled "Default values. Check your fittings." because makers differ. FitUp does not check codes or inspect fittings, and it makes no claim that a result meets a code or a specification.

Buck the beaver

Buck is FitUp's mascot: a beaver with safety glasses pushed up on his forehead and a folding rule, precise and a little dry. He asks the questions during setup and keeps one short line on the home screen. One of those lines sums up the app: "Measure twice. I'll do the arithmetic."

Your data

There is no account. Jobs, cut lists, take-out edits, and settings stay on your iPhone. The only information that leaves the phone is about subscriptions: Apple processes payments, and RevenueCat records subscription status under a random ID. The privacy policy has the details.

FitUp is not affiliated with any fitting maker, tool company, union, or trade school.