What Size Pilot Hole For a 8 Screw
0.0938" in softwood, 0.1094" in hardwood
- #8 wood screw (shank diameter 0.164")
Methodpilot hole sized to roughly the screw's root diameter in softwood, slightly larger in denser hardwood to avoid splitting.
Size up for wood close to an edge or end grain, where splitting risk is highest regardless of the general-purpose figure.
A #8 wood screw wants a 0.0938" pilot hole in softwood or 0.1094" in hardwood — 3/32" and 7/64" respectively — and #8 is the gauge most general cabinetry and furniture assembly defaults to when a project doesn't specify anything more particular.
Why this one specifically
Across the screw gauges this site covers (#6 through #12), the softwood-to-hardwood pilot spread holds at exactly 1/64" (0.015625") at every single size, and #8 sits right in the middle of that table — light enough not to be overkill for cabinet-grade joinery, heavy enough to hold real structural loads in face-frame and carcass assembly. That middle position is exactly why it's the default: it's the gauge most screw boxes at a hardware store are stocked in bulk, and the one most cabinetmaking references use as their baseline example.
What moves the number
Species density is the real variable behind the softwood/hardwood split — a screw driven into something unusually dense (hard maple, hickory) without pre-drilling at all, or drilled undersized, is the most common cause of a snapped screw head in this gauge range.
See the pilot hole for a #6 screw for the lighter size and a #10 screw for the next step up, and the wood screw gauge sizing reference for the full table.