Conduit Bending Calculator
Offset, 3-bend saddle, and 90-degree stub-up math. Distance between bends, shrink, and back-of-bend marks. Free, no account required.
Bend Type
How far the run must shift to clear the obstacle.
12" between marks
Measure between the two bend marks.
How the math works
- Offset: distance between bends = offset depth × the multiplier for the chosen angle. The exact value is offset / sin(angle).
- Shrink: the offset pulls the end of the conduit back. Deduct the shrink from your end measurement before marking.
- 3-bend saddle: 45° center bend with 22.5° outer bends. Outer marks sit 2.5× the obstacle height from center.
- 90° stub: back-of-bend mark = stub height − take-up. Take-up depends on conduit size and bender.
Check your bender
Take-up and multiplier values vary slightly by bender brand and conduit type. Always confirm against the markings stamped on your bender before cutting an expensive run.
Practice bending and conduit problems with 1,600+ NEC questions
Timed NEC practice sessions and step-by-step explanations.
Start Practicing Free →Get NEC Study Tips + Free Practice Questions
NEC study tips, practice questions, and study resources. Unsubscribe anytime.
No spam. Unsubscribe anytime.
Conduit bending values use standard trade multipliers and EMT take-up figures. Confirm against your specific bender and conduit. Not a substitute for manufacturer instructions.
How the conduit bending calculation works
Conduit bending layout uses geometric relationships. For offset layout, use the multiplier specified by the applicable bender instructions or the project’s approved layout method.
Use the shrink allowance specified by the bender manufacturer or verified for the selected bending method.
Use the saddle layout and take-up dimensions specified by the bender manufacturer or verified with the equipment in use.
Step by step
- 1
Pick the bend angle
30 degrees is the general-purpose offset. Shallower angles pull easier and take more length, steeper angles fit tighter spaces.
- 2
Multiply for spacing
Use the multiplier specified by the applicable bender instructions or approved layout method.
- 3
Add the shrink
Use the shrink allowance specified by the bender manufacturer or verified for the selected bending method.
- 4
Mark the conduit
Measure from the end to the first mark, then the calculated distance to the second.
- 5
For a 90, subtract take-up
Use the take-up marked on or specified for the bender in use.
- 6
Respect the bend limits
358.24 for EMT and 344.24 for RMC require the radius of the curve not be less than Chapter 9 Table 2, and 358.26 limits a run to 360 degrees total between pull points.
Worked example
Make a 6 inch offset in 3/4 inch EMT using 30 degree bends. Where do the marks go and how much length is lost?
- Consult the applicable bender instructions for the offset multiplier.
- Multiply the 6-inch offset by that approved multiplier to determine bend spacing.
- Consult the bender instructions for the shrink allowance.
- Add the verified shrink allowance before marking the conduit.
Answer: Use the verified multiplier and shrink allowance for the bender and method in use. Marking values can vary by equipment and layout method.
How this is tested on the exam
Practical and written examination components, if any, vary by jurisdiction. For code compliance, observe the applicable bend-radius and total-bend limits in the relevant raceway article.
Frequently asked questions
Where do the offset multipliers come from?
Use the multiplier supplied by the applicable bender instructions or approved layout reference.
What is shrink and why does it matter?
Bending an offset shortens the effective straight-line length of the conduit, because part of the run is now traveling diagonally. If you do not add the shrink amount to your measurement before marking, the finished piece lands short of the box.
What is take-up on a 90 degree bend?
Take-up is a bender-specific dimension. Consult the markings or instructions for the specific bender to determine take-up.
How many bends are allowed between pull points?
358.26 limits EMT to not more than the equivalent of four quarter bends, 360 degrees total, between pull points. Article 344.26 sets the same limit for rigid metal conduit. Minimum bend radius comes from Chapter 9 Table 2.
Related calculators
Related NEC guides
Studying for your electrician exam?
The math on this page shows up on the real test. Practice 1,600+ exam questions with full 2023 NEC references, free to start.
Try Free Practice Questions →