Why is my offset coming out short?

Almost always shrink. Bending an offset pulls the far end back toward the bends, so the run is shorter than the flat length you measured. Add the shrink figure to your original measurement before you make the first mark.

What angle should I use for a small offset?

A smaller angle gives a longer, gentler jog and less shrink, which is easier to pull off cleanly in a tight space. 22.5° and 30° cover most box and panel offsets; 45° is for clearing something deep in a short run.

Does shrink apply to saddles too?

Yes, but the amount is different. A three-point saddle uses the shrink of its outer bend angle, applied to the depth. Use the saddle calculator rather than the offset shrink for those.

Is the multiplier the same for every conduit size?

The geometric multiplier is. It comes only from the angle, so 30° is always ×2 whether you are bending half-inch EMT or two-inch rigid. Take-up and gain change with the bender and the pipe; the offset multiplier does not.

Conduit offset calculator

To bend an offset, enter the height you need to clear (the rise) and the angle of your two bends. The distance between the marks is the rise times the offset multiplier for that angle; the shrink is how much the run pulls in, which you add to your measurement so the far end lands where you want it.

Worked example

Say you need a 6 inch offset at 30° to clear a box. The multiplier for 30° is exactly 2, so your two marks go 12 inches apart (6 × 2). The shrink for 30° is about 0.268 inch per inch of rise, so 6 × 0.268 ≈ 1 5/8 inches. Make your first mark 1 5/8 inches further along than your original measurement, then the second mark 12 inches past the first, and bend the same angle at each.

The formula

The distance between the marks is the rise divided by the sine of the angle:

distance = rise ÷ sin θ

The offset is the vertical leg of a right triangle and the pipe between the marks is the hypotenuse, so the hypotenuse is the rise over sin θ. Shrink is the difference between that hypotenuse and its horizontal run, rise × (1/sin θ − 1/tan θ). That is all the math there is — no table, no chart, just the triangle.

Exact multiplier vs. the field rule

Shop multipliers are rounded for mental math. They are fine for small offsets; the rounding starts to matter on large offsets and tight runs, where an eighth of an inch of drift moves the far end noticeably.

Angle	Multiplier	Field rule	Shrink / in	Field rule
10°	5.759	6	0.087 in	1/16"
22.5°	2.613	2.6	0.199 in	3/16"
30°	2.000	2	0.268 in	1/4"
45°	1.414	1.4	0.414 in	3/8"
60°	1.155	1.15	0.577 in	1/2"

Questions

Why is my offset coming out short?: Almost always shrink. Bending an offset pulls the far end back toward the bends, so the run is shorter than the flat length you measured. Add the shrink figure to your original measurement before you make the first mark.
What angle should I use for a small offset?: A smaller angle gives a longer, gentler jog and less shrink, which is easier to pull off cleanly in a tight space. 22.5° and 30° cover most box and panel offsets; 45° is for clearing something deep in a short run.
Does shrink apply to saddles too?: Yes, but the amount is different. A three-point saddle uses the shrink of its outer bend angle, applied to the depth. Use the saddle calculator rather than the offset shrink for those.
Is the multiplier the same for every conduit size?: The geometric multiplier is. It comes only from the angle, so 30° is always ×2 whether you are bending half-inch EMT or two-inch rigid. Take-up and gain change with the bender and the pipe; the offset multiplier does not.

Related tools

Three-point saddle calculator — for a round obstruction.
Rolled offset calculator — when the offset is not in one plane.
Conduit bending multipliers — the full reference table.