Conduit Bending Calculator

90° Stub-Up

• Formula: Mark = Stub Height + Deduction (multiplier)
• Example: For 12" stub with 3/4" EMT: Mark at 12" + 5" = 17" from end
• Arrow Mark: Place arrow on bender at your mark
• Star/Rim Mark: Some benders use different reference points

Offset Bends

• Purpose: Move conduit around obstacles or change elevation
• Matching Angles: Both bends must be the same angle
• Shrinkage: Offset uses less conduit length than straight run
• 30° Most Common: Good balance of clearance and ease of bending
• Formula: Distance = Depth × Multiplier

3-Bend Saddle

• Purpose: Pass over pipes or other obstructions
• Center Bend: 45° bend at center of obstruction
• Outside Bends: 22.5° bends on each side
• Spacing: Outside bends at 2.5× height from center
• Mark Order: Make center bend first, then outside bends

Back-to-Back 90s

• Purpose: Create U-shaped run (e.g., conduit up and down wall)
• Calculation: Distance between bends minus two deductions
• Bending: Make first bend, measure for second, flip conduit
• Alignment: Ensure both bends are in same plane

Bending Tips

• Measure Twice: Double-check all measurements before bending
• Start Simple: Practice basic bends before complex saddles
• Avoid Overbending: Easier to add than remove a bend
• Support Properly: Use foot pressure evenly on bender
• Check Level: Use level to verify 90° bends
• Mark Clearly: Use permanent marker for visibility
• Account for Gain: Advanced: gain occurs in back-to-back bends

Common Mistakes

• Wrong multiplier for conduit size
• Forgetting to account for shrinkage in offsets
• Not matching offset bend angles
• Bending too fast causing conduit kinks
• Making saddle outside bends before center
• Using wrong reference mark on bender

NEC Considerations

• NEC 358.24: Maximum 360° total bends between boxes
• NEC 358.28: Minimum bending radius per NEC Table 2
• Support: Support within 3 ft of box, every 10 ft thereafter
• Fill: Maintain proper fill ratio per NEC Chapter 9