These are general workshop reference charts. If a product page lists an exact size or compatibility note, use that first.
Common drill bit sizes (fractional ↔ metric)
| Fractional (in) | Metric (mm) | Typical use |
|---|
| 1/16 | 1.6 | Pilot holes, small hardware |
| 1/8 | 3.2 | General pilot holes, #6–8 screws |
| 3/16 | 4.8 | #8–10 screws, wall anchors |
| 1/4 | 6.4 | #12–14 screws, carriage bolts |
| 5/16 | 7.9 | Lag shield anchors |
| 3/8 | 9.5 | 1/4 in bolts, dowels |
| 1/2 | 12.7 | 1/4 in lag bolts, large dowels |
Socket drive sizes
| Drive | Typical fastener range | Best for |
|---|
| 1/4 in | 4–14 mm | Trim, electronics, small hardware |
| 3/8 in | 8–19 mm | General assembly, engine bays, furniture |
| 1/2 in | 10–32 mm | Suspension, plumbing unions, breakers |
Wood screw gauge ↔ pilot hole
| Screw gauge | Shank dia. (approx.) | Pilot hole (hardwood) |
|---|
| #6 | 3.5 mm | 2.5 mm |
| #8 | 4.0 mm | 3.0 mm |
| #10 | 4.9 mm | 3.5 mm |
| #12 | 5.5 mm | 4.0 mm |
Battery platforms
Stick to one platform per household or crew. A 20V MAX pack does not fit an 18V tool even when the number sounds the same — "MAX" is a marketing label for nominal 18V. Check the product page compatibility note before ordering bare tools.
More references: socket set sizes explained · tool guide.