By Blissom · Updated 2026-11-04
Layout values: check them against your own bender, on scrap first.
Why the multiplier is exactly 2
The multiplier for any offset is 1 ÷ sin θ. The sine of 30° is exactly one half, so the multiplier is exactly 2. Every other sticker angle carries a rounded number; this one does not.
That matters on a ladder with a pencil in your teeth. Doubling 7-3/8" in your head is easy; multiplying it by 2.6 or 1.4 is not. Fewer arithmetic slips is the main reason 30° became the habit angle.
between bends = depth × 2 · shrink = depth × 1/4"
30° offset chart, 1/2" to 24"
Field values: the 2 multiplier and 1/4" shrink per inch from bender guides, rounded to the nearest 1/16". Advance is how far along the run the offset travels, center of bend to center of bend.
| Depth | Between bends | Shrink | Horizontal advance |
|---|---|---|---|
| 1/2" † | 1" * | 1/8" | 7/8" |
| 1" † | 2" | 1/4" | 1-3/4" |
| 1-1/2" | 3" | 3/8" | 2-5/8" |
| 2" | 4" | 1/2" | 3-7/16" |
| 2-1/2" | 5" | 5/8" | 4-5/16" |
| 3" | 6" | 3/4" | 5-3/16" |
| 3-1/2" | 7" | 7/8" | 6-1/16" |
| 4" | 8" | 1" | 6-15/16" |
| 4-1/2" | 9" | 1-1/8" | 7-13/16" |
| 5" | 10" | 1-1/4" | 8-11/16" |
| 5-1/2" | 11" | 1-3/8" | 9-1/2" |
| 6" | 12" | 1-1/2" | 10-3/8" |
| 7" | 14" | 1-3/4" | 12-1/8" |
| 8" | 16" | 2" | 13-7/8" |
| 9" | 18" | 2-1/4" | 15-9/16" |
| 10" | 20" | 2-1/2" | 17-5/16" |
| 11" | 22" | 2-3/4" | 19-1/16" |
| 12" | 24" | 3" | 20-13/16" |
| 14" | 28" | 3-1/2" | 24-1/4" |
| 16" | 32" | 4" | 27-11/16" |
| 18" | 36" | 4-1/2" | 31-3/16" |
| 20" | 40" | 5" | 34-5/8" |
| 22" | 44" | 5-1/2" | 38-1/8" |
| 24" | 48" | 6" | 41-9/16" |
* Marks under 2" apart: the shoe cannot make the second bend without bending into the first. † Shallower than roughly 1-1/4", the two 30° arcs overlap on a 1/2" EMT shoe with a 4-5/8" radius, so the table value cannot be bent as two separate bends there.
Marks on 1/2", 3/4" and 1" EMT
The multiplier does not care what size the pipe is. What changes between sizes is how shallow you can go and how much the bender fights you. Each example measures from the end of the conduit to the point where the offset has to be finished, then puts both marks on the pipe for the arrow.
1/2" EMT: clearing a 3" deep junction box on the ceiling, 36" from the end
- Between bends: 3" × 2 = 6".
- Shrink: 3" × 1/4" = 3/4".
- First mark: 36" + 3/4" − 6" = 30-3/4" from the end.
- Second mark: 30-3/4" + 6" = 36-3/4". Bend 30°, roll 180°, bend 30°.
The offset advances 5-3/16" along the run. On a 1/2" shoe, 30° offsets shallower than about 1-1/4" are not practical.
3/4" EMT: clearing a 4" water line crossing the wall, 48" from the end
- Between bends: 4" × 2 = 8".
- Shrink: 4" × 1/4" = 1".
- First mark: 48" + 1" − 8" = 41" from the end.
- Second mark: 41" + 8" = 49". Bend 30°, roll 180°, bend 30°.
The offset advances 6-15/16" along the run. On a 3/4" shoe, 30° offsets shallower than about 1-1/2" are not practical.
1" EMT: clearing a 6" duct flange, 60" from the end
- Between bends: 6" × 2 = 12".
- Shrink: 6" × 1/4" = 1-1/2".
- First mark: 60" + 1-1/2" − 12" = 49-1/2" from the end.
- Second mark: 49-1/2" + 12" = 61-1/2". Bend 30°, roll 180°, bend 30°.
The offset advances 10-3/8" along the run. On a 1" shoe, 30° offsets shallower than about 1-3/4" are not practical.
The 1/4" shrink rule vs the exact value
Shrink per inch is tan(θ ÷ 2). For 30° that is tan 15° = 0.2679, a little over the 1/4" the sticker uses. The rule always comes up short, and the shortfall grows with depth:
| Depth | Shrink at 1/4"/in | Exact shrink | Short by |
|---|---|---|---|
| 6" | 1-1/2" | 1-5/8" | 1/8" |
| 12" | 3" | 3-3/16" | 3/16" |
| 24" | 6" | 6-7/16" | 7/16" |
Under about 6" of depth the difference is a sixteenth or so and disappears in the bend itself. On deep offsets that land right at a box or fitting, add the extra or check with the shrink calculator. Note that the multiplier carries no such error at 30°: a sticker-math 30° offset bent to a true 30° comes out at exactly the depth you wanted.
Shallowest 30° offset per shoe
Each bend uses up some conduit along the shoe's arc. When the offset is shallow, the second arc would start before the first one ends. The depth where they just touch is about 2 × R × (1 − cos 30°), with R the centerline radius of the shoe:
| EMT bender | Shoe radius | Minimum 30° depth |
|---|---|---|
| 1/2" (Klein 51606) | 4-5/8" | 1-1/4" |
| 3/4" (Klein 51607) | 5-1/2" | 1-1/2" |
| 1" (Greenlee 842AH) | 6-1/2" | 1-3/4" |
An estimate for these particular shoes; other benders have other radii. Below these depths drop to 22.5° or 10°.
30° against 22.5° and 45°
The same 6" offset bent three ways:
| Angle | Between bends | Shrink | Advance | Toward 360° |
|---|---|---|---|---|
| 22.5° | 15-5/8" | 1-1/8" | 14-1/2" | 45° |
| 30° | 12" | 1-1/2" | 10-3/8" | 60° |
| 45° | 8-3/8" | 2-1/4" | 6" | 90° |
- Pick 22.5° when wire pulls are already heavy or the offset is in plain sight; it reads softer and costs 45° instead of 60°.
- Pick 45° when there is no room along the run for a 30° advance, typically deep offsets around beams.
- Stay at 30° for everything in between. A run can hold 6 of them before it hits the 360° between pull points (NEC 358.24(B) in the 2023 edition, 358.26 in 2020) with nothing else in it.
Bending 29° or 31° by mistake
The depth you get is the spacing between the bends times the sine of the angle you actually bent. With the marks 8" apart for a 4" offset:
| Both bends at | Depth you get | Error |
|---|---|---|
| 28° | 3-3/4" | −1/4" |
| 29° | 3-7/8" | −1/8" |
| 31° | 4-1/8" | +1/8" |
| 32° | 4-1/4" | +1/4" |
About 1/8" per degree on this offset, which is why a 30° offset is forgiving. The error that ruins a 30° offset is rarely the angle; it is one bend at 30° and the other at 28°, which leaves the tail of the pipe climbing. Sight down the conduit after the second bend and tweak the shallow one.
Sources: NEC 2023 358.24 and Chapter 9, Table 2; Klein Tools Conduit Bender Guide (stub take-up, offset multipliers and shrink, saddles). Method.
Questions electricians ask
What is the multiplier for a 30 degree offset?
2. Multiply the depth by 2 to get the distance between the two bend marks: a 5" offset has its marks 10" apart. Because sin 30° is exactly 0.5, this is the true value, not a rounding.
How much does a 30 degree offset shrink?
The trade rule is 1/4" per inch of depth. The sharp-corner value is 0.268" per inch, so the rule runs short by about 3/16" on a 12" offset.
How do you bend a 30 degree offset on 3/4 EMT?
Same multiplier and shrink as every size. For a 4" offset that has to clear something 48" from the end: bends 8" apart, shrink 1", first mark at 41" and second at 49". On a 3/4" shoe the offset needs to be at least about 1-1/2" deep.
What is the 30 degree offset formula?
Distance between bends = depth × 2. Shrink = depth × 1/4". Horizontal advance = depth ÷ tan 30°, about 1.732 × depth.
Is there a 30 degree offset chart for 1/2 EMT?
The chart on this page works for 1/2", 3/4" and 1" EMT alike: the multiplier and shrink do not depend on conduit size. Only the minimum depth changes, because larger shoes have a larger radius.
30° offsets with marks from the pipe end
- Both marks measured from the end of the conduit, shrink already added
- Corrected for the radius of your own shoe
- Warns when the two marks are too close to bend
- Any angle, not only the stickers, and works offline
Android only. There is no iPhone version yet; the free calculators on this site work on any phone.
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