Conduit Bend Calculator
Professional conduit bending calculator for electrical installations. Calculate bend angles, offsets, kick measurements, and determine the right bending techniques for EMT, rigid, and flexible conduit.
Conduit Size
3/4"
Type
EMT
Deduct
"
Gain
"
Common Multipliers
10° = ×6.0 | 15° = ×3.9 | 22.5° = ×2.6
30° = ×2.0 | 45° = ×1.4 | 60° = ×1.15
Bend Radius
Minimum bend radius: "
(Based on NEC Table 300.4(B))
NEC Requirements
• Maximum 360° total bends between pull points
• Maintain minimum bend radius to prevent damage
• No more than four 90° bends in one run
Tips
• Measure twice, bend once
• Practice on scrap pieces first
• Use steady, continuous pressure
• Mark all bend points before starting
90° Bend
Standard stub-up or back-to-back bend. Use deduct to calculate marking point from end of conduit.
Offset Bend
Two bends in same plane to navigate around obstacles. Distance = Offset × Multiplier.
Back-to-Back
Two 90° bends in opposite directions. Commonly used for panel connections.
Kick (3-Point Saddle)
Three bends to go over obstacles. Center bend is twice the side bend angles.
Developed Length
Arc length of the bent section. Useful for calculating total conduit needed.
How to Calculate Conduit Bends: Step-by-Step
Accurate conduit bending prevents kinks, maintains code compliance, and ensures a professional installation. Here is how to calculate the key measurements for offset bends.
Step 1: Measure the Offset Distance
Determine how far the conduit needs to move from one plane to another. This is the perpendicular distance between the starting and ending positions. For example, clearing a 6-inch obstruction requires a 6-inch offset.
Step 2: Choose the Bend Angle
Common offset angles are 10, 22.5, 30, and 45 degrees. Shallower angles create gentler bends that are easier to pull wire through. 30 degrees is the most commonly used angle for standard offsets.
Step 3: Calculate the Distance Between Bends
Multiply the offset height by the multiplier for your angle: 6.0 for 10 degrees, 2.6 for 22.5 degrees, 2.0 for 30 degrees, and 1.4 for 45 degrees. This gives the center-to-center distance between your two bend marks.
Step 4: Mark the Conduit
Place your first mark where the offset begins. Measure the calculated distance and place the second mark. Both bends will be made at the same angle but in opposite directions.
Step 5: Account for Shrinkage
Offsets shorten the overall conduit length. The shrinkage amount depends on the angle: 1/16" per inch for 10 degrees, 3/16" per inch for 22.5 degrees, 1/4" per inch for 30 degrees, and 3/8" per inch for 45 degrees. Add this to your total conduit length.
Formula
Distance Between Bends = Offset Height x Multiplier
Where: Multiplier = 6.0 (10 deg), 2.6 (22.5 deg), 2.0 (30 deg), 1.4 (45 deg). Shrinkage per inch of offset: 1/16" (10 deg), 3/16" (22.5 deg), 1/4" (30 deg), 3/8" (45 deg)
Worked Example
Scenario: You need to bend a 6-inch offset at 30 degrees in 3/4" EMT conduit.
- Step 1: Offset distance = 6 inches
- Step 2: Chosen angle = 30 degrees (multiplier = 2.0)
- Step 3: Distance between bends = 6 x 2.0 = 12 inches
- Step 4: Mark conduit at the starting point, then 12 inches away for the second bend
- Step 5: Shrinkage = 6 x 1/4" = 1.5 inches added to the total run
Result: Place bends 12 inches apart at 30 degrees each, and add 1.5 inches to account for shrinkage in the overall run.
Conduit Bending Questions & Answers
What's the standard deduct for 90-degree bends?
The deduct varies by conduit size and type. For EMT: 1/2" = 5", 3/4" = 6", 1" = 8", 1-1/4" = 11", 1-1/2" = 14", 2" = 16". For rigid conduit, add about 1" to each deduct. These are center-line radius measurements. Always verify with your bender's specifications and practice on scrap pieces.
How do you calculate offset bend measurements?
For offset bends, use the formula: Distance between bends = Offset ÷ sin(angle). For common angles: 10° multiplier = 6, 15° = 3.9, 22.5° = 2.6, 30° = 2, 45° = 1.4. The shrink (conduit used up) = Offset × (multiplier - 1). For a 6" offset at 30°: distance = 6 × 2 = 12", shrink = 6 × 1 = 6".
What's the difference between EMT and rigid conduit bending?
EMT (Electrical Metallic Tubing) is thinner and easier to bend, requiring less force and smaller radius bends. Rigid conduit has thicker walls and requires more force, larger radius bends, and different deduct values. EMT uses compression fittings while rigid uses threaded connections. EMT is more common for interior work, rigid for outdoor and industrial applications.
How many degrees can you bend conduit in one pull?
NEC 358.26 limits total bends to 360° (four 90° bends) between pulling points like boxes or conduit bodies. This prevents excessive stress on wire insulation during pulling. For practical installation, try to keep it under 270° when possible. Use pulling elbows, LBs, or junction boxes to break up long runs with multiple bends.
What tools do I need for conduit bending?
Basic tools: hand bender (hickey) for smaller sizes, mechanical or hydraulic bender for larger conduit, measuring tape, level, permanent marker, and reamer. For precision work: protractor, torpedo level, and conduit bending guide. Electric benders speed up production work. Always use proper PPE and check bender condition before use.
How do you prevent conduit from kinking during bends?
Use proper bending technique: steady, continuous pressure rather than jerky movements. Don't exceed the minimum bend radius for your conduit size. For hand bending, keep your foot placement consistent and apply gradual force. For mechanical benders, ensure proper alignment and use the right die. Practice on scrap pieces first, especially with larger sizes.
What's the minimum bend radius for different conduit sizes?
NEC Table 300.4(B) specifies minimum bend radii. For EMT: 1/2" = 4", 3/4" = 4.5", 1" = 5.3", 1-1/4" = 7.2", 1-1/2" = 8.2", 2" = 9.5". These are one-shot 90° bends. Field bends can have smaller radii but must not damage the conduit or significantly reduce the internal cross-sectional area. Always follow manufacturer specifications.
How do you measure and mark conduit for complex bends?
Start with accurate field measurements and a detailed sketch. Mark all bend points before bending. Use the "measure twice, cut once" principle. For multiple bends, work from a fixed reference point. Account for take-up and gain/shrink in your measurements. Consider making a cardboard template for complex shapes or repetitive bends.
What's the difference between gain and shrink in conduit bending?
Gain is the distance saved when making a 90° bend compared to using two straight pieces with an elbow fitting. Shrink is conduit length lost in offset bends. For 90° bends, gain = (2 × center-line radius) - deduct. For offsets, shrink = offset height × (multiplier - 1). Understanding both helps with accurate conduit length calculations and material estimation.
How do you bend conduit in tight spaces?
In cramped areas, pre-bend conduit when possible or use mechanical benders that require less swing space. Segmented bends (multiple small bends instead of one large bend) can help navigate tight spots. Consider using flexible conduit sections, pulling elbows, or conduit bodies to reduce bending requirements. Plan your routing to minimize difficult bends in confined spaces.
What safety precautions should I take when bending conduit?
Wear safety glasses, work gloves, and steel-toed boots. Check bender condition before use - look for cracks, wear, or damage. Maintain stable footing and body position. Don't over-bend then try to bend back. Use proper lifting techniques for heavy conduit. Be aware of overhead hazards and electrical equipment. Keep work area clean and well-lit. Never use damaged or worn bending equipment.
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