A screw extractor (an “easy-out”) works in reverse: you drill a small pilot hole down the center of the broken fastener, then thread the extractor counter-clockwise into that hole. Its reverse taper wedges tighter as it turns, grabs the walls, and spins the broken piece out the same direction. The two everyday styles — spiral flute and straight flute — are each sold by a number (#1, #2, #3…).
The number is a size step — not the bolt’s diameter. Each extractor number backs out a range of broken fastener sizes, and the same number covers different sizes on each style — a #4 spiral is not a #4 straight. So work the other way around: find the size of your broken bolt or screw, then read across to the extractor whose “removes” range covers it and the pilot hole it calls for.
Reverse-tapered spiral grips harder the more you turn it. Best all-around choice for broken bolts and studs.
Straight splines drive into the pilot hole. Handles harder, more stubborn breaks where a spiral could over-expand.
Drill bit and extractor in one bit — drill the pilot, flip it, back the bolt out. Fast for common sizes.
For screws that still stand proud but whose head is stripped — grips from above instead of a drilled hole.
The everyday workhorse. Find the number whose Removes range covers your broken bolt or screw, drill the pilot straight down the center, and back it out counter-clockwise — start on the small side of the pilot and step up only if it won’t bite. Sizes are inches.
| Extractor | Removes — broken bolt/screw | Pilot drill |
|---|---|---|
| #1 | 3/32–5/32 | 5/64 |
| #2 | 5/32–7/32 | 7/64 |
| #3 | 7/32–9/32 | 5/32 |
| #4 | 9/32–3/8 | 1/4 |
| #5 | 3/8–5/8 | 19/64 |
| #6 | 5/8–7/8 | 13/32 |
| #7 | 7/8–1 1/8 | 17/32 |
| #8 | 1 1/8–1 3/8 | 13/16 |
| #9 | 1 3/8–2 | 1 1/16 |
| #10 | 2 1/8–2 1/2 | 1 5/16 |
| #11 | 2 1/2–3 | 1 9/16 |
| #12 | 3–3 1/2 | 1 15/16 |
Straight splines drive into the pilot hole — good on harder, more stubborn breaks where a spiral could over-expand. The ranges are not the same as the spiral line — a #4 straight (1/2–9/16) is a much bigger tool than a #4 spiral (9/32–3/8). Read this chart on its own.
| Extractor | Removes — broken bolt/screw | Pilot drill |
|---|---|---|
| #1 | 3/16–5/16 | 9/64 |
| #2 | 3/8 | 3/16 |
| #3 | 7/16 | 15/64 |
| #4 | 1/2–9/16 | 5/16 |
| #5 | 5/8 | 3/8 |
| #6 | 3/4 | 15/32 |
| #7 | 7/8 | 9/16 |
Browse everything — spiral & straight flute, drill-outs, damaged-head grips and sets — in Tools › Screw Extractors. Bigger than a #12? Give us a call.
Don’t snap the extractor off in the hole. Screw extractors are hardened and brittle — a broken extractor is far harder to remove than the bolt was, because it won’t drill. If it stops turning and won’t move, back off: add heat and penetrating oil, step up a pilot size, or bring it to us. Force is what breaks them.
