A pipe fitting calculator for the people who actually cut and weld the pipe. Enter what you measured, get the length to cut and where to mark it.
Clear an obstruction in one plane. Travel, advance and the exact length of the straight piece between the two fittings.
Rise and roll at the same time. You get the true offset, the cut length and the clock position to roll the fitting to, so you are not doing trigonometry in your head on a ladder.
A rack of lines going around the same obstruction. Bend them all at the same point and they crowd each other in the diagonal. SpoolCalc tells you how far ahead each line starts so the spacing survives the turn.
Build an elbow out of straight pipe when you cannot get the fitting. Piece lengths, cut face angle, and a wrap-around template with ordinates.
Fish mouth template for a branch entering a run at any angle, from a straight tee to a 30 degree lateral.
Trim a 90 down to the angle you actually need, and get the new takeout to use in the rest of your layout.
Colour carries meaning. Grey is the run you are not touching. Orange is the fitting you buy. Dark is the piece you cut. Read the drawing and you already know the job before you read a single number.
Miter and branch cuts hand you a wrap-around template. Wrap the paper, mark the stations, join the marks, cut the line.
Fitting dimensions follow ASME B16.9, U.S. Customary tables. Long radius, short radius, 45s and tees, from 1/2" through 24". The Fitting Specs screen shows every dimension for the pipe you picked and explains what each one means.
The shortcuts every apprentice learns do not hold everywhere. A 45 elbow is not simply 0.625 × the pipe size below 4", and the standard sets a larger minimum. SpoolCalc reads the table, not the shortcut.
See every formula, the data source and worked examples you can check by hand →
These are nominal values. Always check the fitting in your hand before you cut.
Offset and Fitting Specs are free and stay free. Pro unlocks the rest for one payment and never charges you again. No subscription, no ads, no video to sit through, no account to create.
Questions, or a number that does not look right? Write to tech@clk.company and tell us what you were building. Getting the numbers right matters more to us than anything else in this app.