Pipe math,paid once.

FitterPad works out offsets, rolling offsets and B16.9 take-outs on your iPhone, to the 1/16″, with no signal and no subscription.

Get FitterPad

Coming soon to the App Store. Tap to be told on launch day.

Green chilled-water pipes offsetting around a pump in a basement mechanical room
$14.99once. Not $39.99 every year.
FitterPad showing a 10 inch offset at 45 degrees drawn to scale: travel 1 foot 2 and 1/8 inches, run 10 inches

Type an offset

Travel
1′ 2-1/8″14.142″
Run
10″10.000″
Constant
1.414csc 45°: travel = offset × 1.414
Or try:
Offset10″Run 10″Travel at 45°1′ 2-1/8″

What it works out

Fractions

FitterPad calculator: 5 feet 3 and a half inches plus 2 feet 10 and three quarter inches equals 8 feet 2 and a quarter inches

Feet, inches and sixteenths. Add, subtract, multiply and divide tape measurements and get a tape answer back, with the decimal underneath. Free, for good.

  • Rounds to 1/8, 1/16 or 1/32″
  • Shows the decimal with every answer
  • Multiplies by plain numbers, like × 2-1/2

Offsets at any angle

A 10 inch simple offset drawn at 45 degrees with offset, run and travel labelled

11¼°, 22½°, 30°, 45°, 60°, 90° or any angle you type. Know the run instead? FitterPad works out the angle.

  • Presets for the common fittings
  • Any angle you type, or worked out from the run
  • Drawn to the true angle with your numbers

Rolling offsets

A rolling offset: rise 2 feet, roll 1 foot 1 inch, true offset 2 feet 3 and 5/16 inches, with an end view

Rise and roll give the true offset, then travel and setback. An end view shows how the two make the one.

  • Rise and roll to true offset
  • Travel and setback, by angle or by setback
  • An end view of the roll

Cut lengths

ASME B16.9 take-outs for 6 inch pipe: 90 long radius 9 inches, 45 long radius 3 and 3/4, 90 short radius 6, straight tee 5 and 5/8

Subtracts B16.9 elbow take-outs and your weld gap, so the number you see is the number you cut. It says which fitting it assumed.

  • B16.9 take-outs from ½″ to 24″
  • Long or short radius, set for each end
  • Weld gap from none to 3/16″

Cut elbows

A 12 inch long-radius elbow cut to 37 degrees: take-out 6 inches, outside mark 1 foot 3 and 3/4, center 11 and 5/8, inside 7 and a half

Cutting a 90 down to 37°? Get the take-out, then the outside, center and inside marks to lay out on the fitting.

  • A take-out for any angle
  • Outside, center and inside marks
  • Long or short radius

Checked,line by line

Running a bead round a pipe joint. From The Welding Operator, 1942.
SourceWhat we checkedAgainstResult
ASME B16.9, 201890° and 45° long-radius elbows, ½″ to 24″Table 6.1-140 of 40 match
Straight tees, ½″ to 24″Table 6.1-720 of 20 match
ASME B16.9, 2003Elbows, short-radius elbows and teesTables 12, 15 and 17Same values
ASME B36.10MPipe outside diameters, ½″ to 24″Two published charts20 sizes cross-checked
Trade-calculator manualSimple, rolling and cut-elbow worked examplesIts printed answers7 of 7, to the 1/16″
FitterPadIts own maths testsRun before every release46 of 46 pass

Pay once

$14.99 is less than half of one year on the subscription apps, and you only pay it the one time.

FitterPad Pro, for good

  • Every angle, rolling offsets, take-outs and cut elbows
  • One payment, no subscription, no account
  • Stays unlocked with no signal
  • Family Sharing included
  • The fraction calculator and 45° offsets stay free.
$14.99US price, once
Get FitterPad

Questions

Does it work without a signal?

Yes. Every calculation runs on your phone, and Pro stays unlocked in a basement, a tunnel or a refinery unit.

Is it really one payment?

Yes. $14.99 once (US price) unlocks everything for good, and Family Sharing covers your household. No subscription, no account, no ads.

Where do the take-outs come from?

ASME B16.9 for elbows and tees, ASME B36.10M for pipe outside diameters. Every answer says which fitting it assumed, and Show work lays out the formula.

What’s free?

The feet-inch-fraction calculator and 45° simple offsets, for as long as you have the app.

Does it do metric?

Not yet. FitterPad works in feet, inches and fractions down to 1/32″.

I got a new phone

Open Settings in FitterPad and tap Restore purchase, signed in with the same Apple Account. Pro comes straight back.

What does it collect?

Nothing. No accounts, no tracking, no analytics. Your history stays on your phone. Read the privacy policy.