The bend radius is the radius of the arc the conduit follows through a bend, measured to the pipe's centerline. It is set by your bender head — you cannot bend tighter than the head allows — and the electrical code sets a floor below which you must not go.
Two reasons. First, wire pulling: a tight bend kinks conductors and makes the pull brutal; a generous sweep pulls easy. Second, the code: the NEC limits how tight any bend can be, because crushed or flattened conduit at a bend is a failed installation. Bend tighter than the minimum and the inspector fails it — even if the wire pulled fine.
NEC Chapter 9, Table 2 gives the minimum radius to the centerline for each size. For EMT:
| EMT size | Minimum radius |
|---|---|
| 1/2" | 4" |
| 3/4" | 4-1/2" |
| 1" | 5-3/4" |
| 1-1/4" | 7-1/4" |
| 1-1/2" | 8-1/4" |
| 2" | 9-1/2" |
Standard hand benders are built around these minimums, which is why a 1/2" hand bender and a 2" hydraulic bender feel like different tools — the geometry scales with the pipe.
Radius is not just a code number: it drives gain. A 90° bend saves about 0.4292 × the centerline radius, so the same 90° on a big-radius bender eats more layout length than on a tight one. When precision matters — panel stubs, long runs — use the radius of your bender, not a generic chart.
The conduit can flatten or kink, conductors get damaged during the pull, and the installation fails inspection. The NEC minimums in Chapter 9, Table 2 are hard limits, not suggestions.
No — NEC Table 2 lists each raceway type separately, and rigid (RMC) has larger minimums than EMT for the same trade size. Always check the row for the raceway you are actually bending.
Yes, and for long wire pulls you should. Sweeps and large-radius bends pull dramatically easier than minimum-radius 90s. The code sets a floor, not a ceiling.
Directly: gain on a 90° bend is about 0.4292 times the centerline radius. A bigger radius means more gain, which means more to subtract from your cut length.
Try it free: Open the free conduit bending calculator — all six bend calculators, no sign-up.
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