Conduit Offset, Kick & Saddle Bend Calculator

How it works

Distance between offset bends = rise × multiplier, multiplier = 1 ÷ sin(angle) (10° 5.76, 22.5° 2.61, 30° 2.0, 45° 1.41, 60° 1.15); shrink = rise × (1 − cos) ÷ sin ≈ 1/16, 3/16, 1/4, 3/8, 1/2 in per inch; three-point saddle: outer marks = rise × 2.5 from centre, shrink 3/16″ per inch

An offset moves a conduit run sideways around an obstruction with two equal and opposite bends; trigonometry sets the distance between them — the rise divided by the sine of the angle, which electricians memorise as multipliers (2 for 30°, 1.41 for 45°). Bending also consumes length, so the run “shrinks” by an amount that grows with the angle, and the first mark must be moved that far past where the offset is needed. A three-point saddle clears a pipe by bending 45° in the centre and 22.5° back on either side, with the outer marks 2.5 times the rise away; a four-point saddle is simply two offsets back to back. Shallow angles make the easiest wire pulls but need room; 30° is the everyday compromise. Whatever the angle, both bends must be in the same plane or the run will dog-leg.

Worked example

A 6″ offset at 30° needs the marks 12″ apart (6 × 2) and shrinks the conduit about 1.6″ (the ¼″-per-inch rule says 1½″). To start the offset 40″ from the end, put the first mark at 41.6″ and the second at 53.6″; at 45° the marks would be 8.5″ apart with about 2½″ of shrink.

Frequently asked questions