Drill Bit Chart & Tap Sizes

Drill Bit Chart & Tap Sizes is a fast, comprehensive reference tool for machinists, woodworkers, engineers, mechanics, and DIY makers. Quickly look up standard drill bit dimensions, determine recommended tap drill sizes for internal threads, find clearance hole diameters, and convert fractional and decimal measurements instantly.

COMPLETE DRILL BIT CHART
- Fractional Inch: 1/64 in through 1 in and beyond with decimal and millimeter equivalents
- Wire Gauge Sizes: Number drill sizes from #1 through #80
- Letter Sizes: Complete A through Z drill bit series
- Metric Sizes: Standard metric drill sizes with decimal inch conversions
- Instant search and filtering across all drill size systems

TAP DRILL CHARTS & THREAD SIZES
- Unified National Coarse (UNC) and Unified National Fine (UNF)
- Unified Extra Fine (UNEF) thread specifications
- Metric Coarse (M) and Metric Fine (MF) thread series
- National Pipe Taper (NPT) and National Pipe Straight (NPS) sizes
- Recommended tap drill sizes for standard ~75% thread engagement
- Decimal and millimeter equivalents for every thread specification

CLEARANCE HOLE CHARTS
- Close fit recommendations for precision alignment
- Normal / Free fit recommendations for standard clearance
- Imperial fastener clearance from small machine screws up to large bolts
- Metric fastener clearance from M1.6 through large metric bolts

PRECISION CONVERTER & FRACTION CALCULATOR
- Convert between decimal inches, fractional inches, and millimeters
- Find the closest standard drill bit size for any measured dimension
- View exact difference and tolerance to nearest drill sizes
- Paste values directly from your clipboard for fast calculations

WORKSHOP-READY DESIGN
- Save frequently used tap and drill sizes to your Favorites list
- Fast access to recent search history
- High-contrast, clean layout designed for shop lighting and quick glances
- Built for reliable reference at the workbench, mill, lathe, or drill press