Drill Bit Size Chart

Search fractional number letter and metric drill bit sizes with decimal-inch equivalents.

Fractional-inch sizes are exact conversions. Number, letter, and metric sizes below are the commonly referenced standard sizes — always verify against your specific bit or tap-drill chart for critical work.

About this tool

Drill Bit Size Chart is a single-purpose utility on instant.tw, a free toolbox of calculators, converters, generators, and quick lookups. Everything works in your browser — nothing is uploaded, nothing is stored on a server unless explicitly noted.

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