Find the right drill bit & size, the first time.
Clear tap drill charts, drill bit size tables and honest tool guides for metal, concrete, wood and tile. Built for DIYers and pros who want the hole right.
⌀ Quick tap drill sizes
| Thread | Drill | Decimal |
|---|---|---|
| #10-24 UNC | #25 | 0.1495″ |
| #10-32 UNF | #21 | 0.1590″ |
| 1/4-20 UNC | #7 | 0.2010″ |
| 5/16-18 UNC | F | 0.2570″ |
| 3/8-16 UNC | 5/16″ | 0.3125″ |
| M6 × 1.0 | 5.0 mm | 0.1969″ |
| M8 × 1.25 | 6.8 mm | 0.2677″ |
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Tap Drill Sizes
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- 10-32
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- M6
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Drill Bit Size Charts
Fractional, number, letter and metric sizes with decimals.
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