DDrill Size Chart Tools

No-signup reference tools

Drill Size Chart, Tap Drill Chart, and Thread Reference Tools

Search drill sizes, tap drill recommendations, clearance holes, screw pilot holes, and printable shop charts without signing in.

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Quick tap drill lookup

1/4-20 UNC#70.2010 in / 5.11 mm1/4-28 UNF#30.2130 in / 5.41 mm5/16-18 UNCF0.2570 in / 6.53 mm5/16-24 UNFI0.2720 in / 6.91 mm3/8-16 UNC5/160.3125 in / 7.94 mm3/8-24 UNFQ0.3320 in / 8.43 mm

Core shop references

Drill Size ChartFind fractional, number, letter, and metric drill sizes with decimal inch and millimeter equivalents.Drill Bit Size ChartSearch common drill bit sizes and compare inch, decimal, and metric measurements.Tap Drill ChartLook up recommended tap drill sizes for UNC, UNF, and metric threads.Tap Drill CalculatorEstimate tap drill size from major diameter and pitch, then compare to standard drill sizes.Drill and Tap ChartMatch common taps to drill sizes, decimal equivalents, and working notes.Metric Tap Drill ChartReference metric tap drill sizes for M3 through M12 coarse threads.NPT Tap Drill ChartQuick reference for common NPT pipe tap drill sizes.Clearance Hole ChartCompare close-fit and free-fit clearance holes for common screws and bolts.Thread Size ChartConnect screw and bolt thread sizes to tap drill and pitch references.Thread Pitch ChartCompare common thread pitches and where to use coarse vs fine thread references.Screw Size ChartFind screw size references, pilot holes, and clearance hole starting points.Bolt Size ChartReference common bolt diameters, clearance holes, and related drill sizes.Tap Size ChartMap tap sizes to thread families, tap drill sizes, and calculator pages.Thread Pitch CalculatorConvert threads per inch to pitch and compare metric thread pitch values.Printable Drill Tap ChartPrint compact drill, tap, clearance, and pilot-hole sheets for shop use.

Built for repeat lookup, not one-off trivia

Most search results answer one chart at a time. This site connects drill bits, taps, clearance holes, screw pilot holes, and printable references so a user can move from a thread callout to the next practical shop decision.