Tap Drill Sizes for Metric M-Profile Screw Threads
Tap Drill Sizes for Metric M-Profile Screw Threads (text version)
The same data as the chart above, as a table. Tap drill sizes1, theoretical and probable percent of thread, and probable hole size for each tap.
| Tap Size | Tap Drill Size | Decimal Equiv. of Tap Drill (in) | Theoretical Percent of Thread | Probable Mean Oversize (in) | Probable Hole Size (in) | Probable Percent of Thread* |
|---|---|---|---|---|---|---|
| M1.6x0.35 | 1.20mm | .0472 | 88% | .0014 | .0486 | 80% |
| 1.25mm | .0492 | 77% | .0014 | .0506 | 69% | |
| M2x0.4 | 1/16 | .0625 | 79% | .0015 | .0640 | 72% |
| 1.60mm | .0630 | 77% | .0017 | .0647 | 69% | |
| 52 | .0635 | 74% | .0017 | .0652 | 66% | |
| M2.5x0.45 | 2.05mm | .0807 | 77% | .0019 | .0826 | 69% |
| 46 | .0810 | 76% | .0019 | .0829 | 67% | |
| 45 | .0820 | 71% | .0019 | .0839 | 63% | |
| M3x0.5 | 40 | .0980 | 79% | .0023 | .1003 | 70% |
| 2.5mm | .0984 | 77% | .0023 | .1007 | 68% | |
| 39 | .0995 | 73% | .0023 | .1018 | 64% | |
| M3.5x0.6 | 33 | .1130 | 81% | .0026 | .1156 | 72% |
| 2.9mm | .1142 | 77% | .0026 | .1168 | 68% | |
| 32 | .1160 | 71% | .0026 | .1186 | 63% | |
| M4x0.7 | 3.2mm | .1260 | 88% | .0029 | .1289 | 80% |
| 30 | .1285 | 81% | .0029 | .1314 | 73% | |
| 3.3mm | .1299 | 77% | .0029 | .1328 | 69% | |
| M4.5x0.75 | 3.7mm | .1457 | 82% | .0032 | .1489 | 74% |
| 26 | .1470 | 79% | .0032 | .1502 | 70% | |
| 25 | .1495 | 72% | .0032 | .1527 | 64% | |
| M5x0.8 | 4.2mm | .1654 | 77% | .0032 | .1686 | 69% |
| 19 | .1660 | 75% | .0032 | .1692 | 68% | |
| M6x1 | 10 | .1935 | 84% | .0038 | .1973 | 76% |
| 9 | .1960 | 79% | .0038 | .1998 | 71% | |
| 5mm | .1969 | 77% | .0038 | .2006 | 70% | |
| 8 | .1990 | 73% | .0038 | .2028 | 65% | |
| M7x1 | A | .2340 | 81% | .0038 | .2378 | 74% |
| 6mm | .2362 | 77% | .0038 | .2400 | 70% | |
| B | .2380 | 74% | .0038 | .2418 | 66% | |
| M8x1.25 | 6.7mm | .2638 | 80% | .0041 | .2679 | 74% |
| 17/64 | .2656 | 77% | .0041 | .2697 | 71% | |
| H | .2660 | 77% | .0041 | .2701 | 70% | |
| 6.8mm | .2677 | 74% | .0041 | .2718 | 68% | |
| M10x1.5 | 8.4mm | .3307 | 82% | .0044 | .3351 | 76% |
| Q | .3320 | 80% | .0044 | .3364 | 75% | |
| 8.5mm | .3346 | 77% | .0044 | .3390 | 71% | |
| M12x1.75 | 10.20mm | .4016 | 79% | .0047 | .4063 | 75% |
| Y | .4040 | 76% | .0047 | .4087 | 71% | |
| 13/32 | .4062 | 74% | .0047 | .4109 | 69% | |
| M14x2 | 15/32 | .4688 | 81% | .0048 | .4736 | 76% |
| 12mm | .4724 | 77% | .0048 | .4772 | 72% | |
| M16x2 | 35/64 | .5469 | 81% | .0049 | .5518 | 76% |
| 14mm | .5512 | 77% | .0049 | .5561 | 72% | |
| M20x2.5 | 11/16 | .6875 | 78% | .0050 | .6925 | 74% |
| 17.5mm | .6890 | 77% | .0052 | .6942 | 73% | |
| M24x3 | 13/16 | .8125 | 86% | .0052 | .8177 | 82% |
| 21mm | .8268 | 76% | .0054 | .8322 | 73% | |
| 53/64 | .8281 | 76% | .0054 | .8335 | 73% | |
| M30x3.5 | 1 1/32 | 1.0312 | 83% | .0071 | 1.0383 | 80% |
| 26.5mm | 1.0433 | 77% | .0071 | 1.0504 | 73% | |
| 1 3/64 | 1.0469 | 75% | .0072 | 1.0541 | 70% | |
| M36x4 | 1 17/64 | 1.2656 | 74% | Reaming recommended | ||
* Probable percent of full thread produced in tapped hole using standard drill sizes.
1 Recommended sizes for cutting taps. Hole sizes shown may not suit UNJ and MJ hole requirements.