US Tap and Drill Bit Sizes

[HDF Tech]

US Tap and Drill Bit Size Tap --Fractional Drill--Number Drill--Letter Drill 0-80 ------3/64 - - ------------------------------- 1-64 --------------------- 53 --------------------- 2-56 --------------------- 50 --------------------- 3-48 --------------------- 47 --------------------- 4-40 ------3/32----------- 43 -------------------- 5-40 ----------------------38 --------------------- 6-32 ------7/64 -----------35 -------------------- 8-32 ----------------------29 --------------------- 10-24----- 5/32------------25 -------------------- 10-32----- 5/32------------21 -------------------- 12-24 -----11/64---------- 16 -------------------- 1/4-20---- 13/64----------- 7 -------------------- 1/4-28 ----7/32 ------------3 -------------------- 5/16-18 ---17/64 ----------------------- F ------- 5/16-24 -------------------------------- I -------- 3/8-16 -----5/16---------------------------------- 3/8-24 -----21/64 ---------------------- Q ------- 7/16-14 --- 23/64 ---------------------- U -------- 7/16-20 ----25/64 --------------------------------- 1/2-13 -----27/64 --------------------------------- 1/2-20 -----29/64 --------------------------------- 9/16-12-----31/64 --------------------------------- 9/16-18-----33/64 --------------------------------- 5/8-11----- 17/32 --------------------------------- 5/8-18----- 37/64---------------------------------- 3/4-10 -----21/32 --------------------------------- 3/4-16 -----11/16 ---------------------------------