Tap Drill Sizes
Clearance Hole Drills
Size of Screw   Tap Drill Close Fit Free Fit
No. or Dia. Decimal (inch) TPI Drill Size Decimal (inch) Drill Size Decimal (inch) Drill Size Decimal (inch)
Fractl.Num.
#0 0.06 80 3/64   0.0469 52 0.0635 50 0.07
#1 0.073 64 53 0.0595 48 0.076 46 0.081
#1 0.073 72 53 0.0595 48 0.076 46 0.081
#2 0.086 56 50 0.07 43 0.089 41 0.096
#2 0.086 64 50 0.07 43 0.089 41 0.096
#3 0.099 48 47 0.0785 37 0.104 35 0.11
#3 0.099 56 45 0.082 37 0.104 35 0.11
#4 0.112 36 44 0.086 32 0.116 30 0.1285
#4 0.112 40 3/32 43 0.089 32 0.116 30 0.1285
#4 0.112 48 42 0.0935 32 0.116 30 0.1285
#5 (1/8) 0.125 40 38 0.1015 30 0.1285 29 0.136
#5 0.125 44 37 0.104 30 0.1285 29 0.136
#6 0.138 32 7/64 36 0.1065 27 0.144 25 0.1495
#6 0.138 40 33 0.113 27 0.144 25 0.1495
#8 0.164 32 9/64 29 0.136 18 0.1695 16 0.177
#8 0.164 36 9/64 29 0.136 18 0.1695 16 0.177
#10 0.19 24 5/32 25 0.1495 9 0.196 7 0.201
#10 0.19 32 5/32 21 0.159 9 0.196 7 0.201
#12 0.216 24 11/64 16 0.177 2 0.221 I 0.228
#12 0.216 28 3/16 14 0.182 2 0.221 I 0.228
#14 0.242 20 10 0.1935 D 0.246 F 0.257
#14 0.242 24 13/64 7 0.201 D 0.246 F 0.257
1/4 0.25 20 13/64 7 0.201 F 0.257 H 0.266
1/4 0.25 28 7/32 3 0.213 F 0.257 H 0.266
5/16 0.3125 18 17/64 F 0.257 P 0.323 Q 0.332
5/16 0.3125 24   I 0.272 P 0.323 Q 0.332
3/8 0.375 16 5/16   0.3125 W 0.386 X 0.397
3/8 0.375 24 21/64 Q 0.332 W 0.386 X 0.397
7/16 0.4375 14 23/64 U 0.368 29/64 0.4531 15/32 0.4687
7/16 0.4375 20 25/64   0.3906 29/64 0.4531 15/32 0.4687
1/2 0.5 13 27/64   0.4219 33/64 0.5156 17/32 0.5312
1/2 0.5 20 29/64   0.4531 33/64 0.5156 17/32 0.5312
9/16 0.5625 12 31/64
9/16 0.5625 18 33/64
5/8 0.625 11 17/32
5/8 0.625 18 37/64
3/4 0.75 10 21/32
3/4 0.75 16 11/16
Source: Tap Drill Sizes at efunda.com and BoltDepot.com
See: Drill Sizes
See Also: BoltDepot.com
Metric Tap Drill Sizes
Tap
Size
Tap
Drill
Size
Tap
Size
Tap
Drill
Size
Tap
Size
Tap
Drill
Size
M2 x .4 1.60mm M10 x 1.5 8.5mm M18 x 2.5 15.5mm
M2.5 x .45 2.05mm M10 x 1.25 8.75mm M18 x 1.5 16.5mm
M3 x .5 2.5mm M12 x 1.75 10.25mm M20 x 2.5 17.5mm
M4 x .7 3.3mm M12 x 1.25 10.75mm M20 x 1.5 18.5mm
M5 x .8 4.2mm M14 x 2.0 12mm M24 x 3.0 21mm
M6 x 1.0 5mm M14 x 1.5 12.5mm M30 x 3.5 26.5mm
M8 x 1.25 6.75mm M16 x 2.0 14mm M36 x 4.0 32mm
M8 x 1.0 7mm M16 x 1.5 14.5mm
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last updated 1 Apr 2005