What Drill Bit

Wood screws & fasteners

Wood screws, pocket-hole screws, and lag screws, each with its sizing tool, its chart, and a page for every size. Pick the one you're driving.

Wood screwsPilot holes by gauge (#2–#14) — the finder, the full chart, and a page for every size. Pocket screwsScrew length and thread by material thickness — the selector and the chart. Lag screwsPilot holes by diameter and wood type, plus the shank clearance hole.

Working out screw length?

Lumber sizes → actual board thicknessA “2x4” is really 1½" × 3½". Screw length works off that finished thickness, not the nominal name.

Elsewhere on What Drill Bit

Wall & Masonry hubMetal hubSizes & Charts hubGuides

These are general guidance sizes cross-referenced from common woodworking sources. For structural, load-bearing, or manufacturer-specific work, follow the fastener manufacturer’s or an engineer’s specifications.