Metric Tap Drill Sizes and Percentages of Threads

TAP SIZE TAP DRILL DECIMAL EQUIV. THEOR. % OF THREAD TAP SIZE TAP DRILL DECIMAL EQUIV. THEOR. % OF THREAD TAP SIZE TAP DRILL DECIMAL EQUIV. THEOR. % OF THREAD
M1.6X3.5 1.25mm 0.0492 77 M8X1.25 I 0.272 67 M22X1.5 20.5mm 0.8071 77
1.3mm 0.0512 66 M8X1 7mm 0.2756 77 13/16 0.8125 70
#55 0.052 61 J 0.277 74 M24X3 21mm 0.8268 77
M1.8X.35 1.45mm 0.0571 77 M10X1.5 8.5mm 0.3346 77 27/32 0.8438 66
1.5mm 0.0591 66 R 0.339 71 M24X2 22mm 0.8661 77
#53 0.0595 64 M10X1.25 8.75mm 0.3445 77 7/8 0.875 68
M2X.4 1.6mm 0.063 77 S 0.348 71 M27X3 24mm 0.9449 77
#52 0.0635 74 M12X1.75 13/32 0.4062 74 61/64 0.9531 72
M2.2X.45 1.75mm 0.0689 77 Z 0.413 66 M27X2 25mm 0.9843 77
#50 0.07 72 M12X1.25 27/64 0.4219 79 63/64 0.9844 77
M2.5X.45 2.05mm 0.0807 77 11mm 0.4331 62 M30X3.5 26.5mm 1.0433 77
#45 0.082 71 M14X2 12mm 0.4724 77 1 1/16 1.0625 66
M3X.5 2.5mm 0.0984 77 31/64 0.4844 65 M30X2 28mm 1.1024 77
#39 0.0995 73 M14X1.5 12.5mm 0.4921 77 1 7/64 1.1094 70
M3.5X.6 2.9mm 0.1142 77 1/2 0.5 67 M33X3.5 29.5mm 1.1614 77
#32 0.116 71 M16X2 14mm 0.5512 77 1 11/64 1.1719 71
M4X.7 3.3mm 0.1299 77 9/16 0.5625 66 M33X2 31mm 1.2205 77
3.4mm 0.1339 66 M16X1.5 14.5mm 0.5709 77 1 15/64 1.2344 63
#29 0.136 60 37/64 0.5781 68 M36X4 32mm 1.2598 77
M4.5X.75 3.75mm 0.1476 77 M18X2.5 15.5mm 0.6102 77 1 17/64 1.2656 74
#25 0.1495 72 5/8 0.625 65 M36X3 1 19/64 1.2969 78
M5X.8 4.2mm 0.1654 77 M18X1.5 16.5mm 0.6496 77 33mm 1.2992 77
#18 0.1695 67 21/32 0.6562 68 1 5/16 1.3125 68
M6X1 5mm 0.1969 77 M20X2.5 17.5mm 0.689 77 M39X4 1 3/8 1.375 78
#8 0.199 73 45/64 0.7031 66 35mm 1.378 77
M7X1 6mm 0.2362 77 M20X1.5 18.5mm 0.7283 77 1 25/64 1.3906 71
B 0.238 74 47/64 0.7344 69 M39X3 36mm 1.4173 77
M8X1.25 6.75mm 0.2657 77 M22X2.5 19.5mm 0.7677 77 1 27/64 1.4219 74
6.8mm 0.2677 74 25/32 0.7812 66