LLavigne Labs
Shop charts

Inch tap drills

UNC / UNF, #0 to 1/2 in. Drill designation with decimal inches.
Lavigne Labs
Size – TPISeriesTap drillDecimal inHard mat.Decimal inClose clear.Decimal inFree clear.Decimal in
#0-80UNF#56⌀0.0465#55⌀0.052#52⌀0.0635#50⌀0.07
#1-64UNC#53⌀0.0595#53⌀0.0595#48⌀0.076#46⌀0.081
#1-72UNF#53⌀0.05951/16⌀0.0625#48⌀0.076#46⌀0.081
#2-56UNC#50⌀0.07#50⌀0.07#43⌀0.089#41⌀0.096
#2-64UNF#50⌀0.07#49⌀0.073#43⌀0.089#41⌀0.096
#3-48UNC#47⌀0.0785#46⌀0.081#37⌀0.104#35⌀0.11
#3-56UNF#45⌀0.082#45⌀0.082#37⌀0.104#35⌀0.11
#4-40UNC#43⌀0.089#43⌀0.089#32⌀0.116#30⌀0.1285
#4-48UNF#42⌀0.09353/32⌀0.0938#32⌀0.116#30⌀0.1285
#5-40UNC#38⌀0.1015#37⌀0.104#30⌀0.1285#29⌀0.136
#5-44UNF#37⌀0.104#36⌀0.1065#30⌀0.1285#29⌀0.136
#6-32UNC#36⌀0.1065#34⌀0.111#27⌀0.144#25⌀0.1495
#6-40UNF#33⌀0.113#32⌀0.116#27⌀0.144#25⌀0.1495
#8-32UNC#29⌀0.136#29⌀0.136#18⌀0.1695#16⌀0.177
#8-36UNF#29⌀0.136#28⌀0.1405#18⌀0.1695#16⌀0.177
#10-24UNC#25⌀0.1495#23⌀0.154#9⌀0.196#7⌀0.201
#10-32UNF#21⌀0.159#19⌀0.166#9⌀0.196#7⌀0.201
#12-24UNC#16⌀0.177#15⌀0.18#2⌀0.221#1⌀0.228
#12-28UNF#14⌀0.182#13⌀0.185#2⌀0.221#1⌀0.228
1/4-20UNC#7⌀0.201#4⌀0.209F⌀0.257H⌀0.266
1/4-28UNF#3⌀0.2137/32⌀0.2188F⌀0.257H⌀0.266
5/16-18UNCF⌀0.25717/64⌀0.2656P⌀0.323Q⌀0.332
5/16-24UNFI⌀0.272J⌀0.277P⌀0.323Q⌀0.332
3/8-16UNC5/16⌀0.3125P⌀0.323W⌀0.386X⌀0.397
3/8-24UNFQ⌀0.332R⌀0.339W⌀0.386X⌀0.397
7/16-14UNCU⌀0.368V⌀0.37729/64⌀0.453115/32⌀0.4688
7/16-20UNF25/64⌀0.3906X⌀0.39729/64⌀0.453115/32⌀0.4688
1/2-13UNC27/64⌀0.42197/16⌀0.437533/64⌀0.515617/32⌀0.5312
1/2-20UNF29/64⌀0.453129/64⌀0.453133/64⌀0.515617/32⌀0.5312

Tap drill in the red column is the standard (about 75%) drill; the hard-material column is the next size up. Close and free are clearance-hole fits.

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