Tap size Drilling chart

The tap size chart provides a list of standard size taps, specifying the bore and thread spacing, for fractional, metric, and screw sizes. The decimal equivalents of the diameters are shown in both English and Metric units. Partial sizes are listed in inches, while metric sizes are listed in millimeters following the letter "Chiliad". A screw size number corresponds to a bore which is larger for a higher screw size. The thread spacing, which may be coarse or fine, is listed later on the bore. In the partial and screw size systems, the thread count is used, measured in threads per inch. The metric system uses the thread pitch, which is the distance between threads, measured in millimeters. For each thread count, the equivalent thread pitch is provided and for metric taps, the approximate thread count is shown based on the pitch. Lastly, the recommended tap drill size is provided for each standard tap size. This size drill scrap should be used for drilling the initial hole that will and so be tapped.

Tap size Diameter (in) Diameter (mm) Thread count (TPI) Thread pitch (mm) Tap drill size
#0000-160 0.0210 0.5334 160 0.159 ane/64 in
#000-120 0.0340 0.8636 120 0.212 #71
M1x0.two 0.0394 1.0000 ~127 0.200 0.8 mm
M1x0.25 0.0394 1.0000 ~102 0.250 0.75 mm
M1.1×0.25 0.0433 1.1000 ~102 0.250 0.85 mm
M1.1×0.2 0.0433 1.k ~127 0.200 0.9 mm
#00-90 0.0470 1.1938 90 0.282 #65
M1.ii×0.2 0.0472 ane.2000 ~127 0.200 ane mm
M1.two×0.25 0.0472 1.2000 ~102 0.250 0.95 mm
M1.four×0.2 0.0551 1.4000 ~127 0.200 1.2 mm
M1.4×0.3 0.0551 1.4000 ~85 0.300 1.1 mm
#0-80 0.0600 1.5240 80 0.318 three/64 in
M1.half-dozen×0.2 0.0630 1.6000 ~127 0.200 one.four mm
M1.6×0.35 0.0630 1.6000 ~73 0.350 ane.25 mm
M1.8×0.two 0.0709 1.8000 ~127 0.200 1.6 mm
M1.viii×0.35 0.0709 i.8000 ~73 0.350 1.45 mm
#one-64 0.0730 one.8542 64 0.397 #52
#ane-72 0.0730 i.8542 72 0.353 #53
M2x0.25 0.0787 2.0000 ~102 0.250 1.75 mm
M2x0.four 0.0787 two.0000 ~64 0.400 ane.six mm
#ii-56 0.0860 2.1844 56 0.454 #fifty
#2-64 0.0860 ii.1844 64 0.397 #50
M2.2×0.25 0.0866 2.2000 ~102 0.250 one.95 mm
M2.2×0.45 0.0866 2.2000 ~57 0.450 1.75 mm
M2.5×0.35 0.0984 two.5000 ~73 0.350 2.1 mm
M2.5×0.45 0.0984 ii.5000 ~57 0.450 ii.05 mm
#three-48 0.0990 2.5146 48 0.529 #47
#3-56 0.0990 2.5146 56 0.454 #45
#four-forty 0.1120 ii.8448 40 0.635 #43
#4-48 0.1120 2.8448 48 0.529 #42
M3x0.35 0.1181 three.0000 ~73 0.350 2.6 mm
M3x0.5 0.1181 three.0000 ~51 0.500 two.5 mm
#five-40 0.1250 3.1750 forty 0.635 #39
#5-44 0.1250 3.1750 44 0.577 #37
M3.5×0.35 0.1378 3.5000 ~73 0.350 three.1 mm
M3.5×0.six 0.1378 iii.5000 ~43 0.600 ii.9 mm
#6-32 0.1380 3.5052 32 0.794 #36
#6-40 0.1380 iii.5052 forty 0.635 #33
M4x0.35 0.1575 four.0000 ~73 0.350 iii.6 mm
M4x0.5 0.1575 4.0000 ~51 0.500 iii.five mm
M4x0.7 0.1575 4.0000 ~37 0.700 3.3 mm
#8-32 0.1640 4.1656 32 0.794 #29
#8-36 0.1640 4.1656 36 0.706 #29
M4.5×0.5 0.1772 iv.5000 ~51 0.500 4 mm
M4.5×0.75 0.1772 4.5000 ~34 0.750 three.8 mm
#10-32 0.1900 4.8260 32 0.794 #21
#10-24 0.1900 iv.8260 24 1.058 #25
M5x0.5 0.1969 5.0000 ~51 0.500 4.5 mm
M5x0.8 0.1969 5.0000 ~32 0.800 iv.2 mm
#12-24 0.2160 5.4864 24 i.058 #17
#12-28 0.2160 five.4864 28 0.907 #15
M5.5×0.five 0.2165 5.5000 ~51 0.500 v mm
M6x0.five 0.2362 half-dozen.0000 ~51 0.500 5.5 mm
M6x0.75 0.2362 6.0000 ~34 0.750 5.ii mm
M6x1 0.2362 vi.0000 ~26 1.000 5 mm
ane/4-20 0.2500 6.3500 20 1.270 #vii
1/4-28 0.2500 half dozen.3500 28 0.907 #3
M7x0.75 0.2756 seven.0000 ~34 0.750 6.2 mm
M7x1 0.2756 7.0000 ~26 ane.000 6 mm
5/16-18 0.3125 vii.9375 18 one.411 F
v/16-24 0.3125 7.9375 24 1.058 I
M8x0.5 0.3150 8.0000 ~51 0.500 7.5 mm
M8x0.75 0.3150 8.0000 ~34 0.750 7.2 mm
M8x1 0.3150 8.0000 ~26 1.000 vii mm
M8x1.25 0.3150 8.0000 ~21 1.250 vi.eight mm
M9x0.75 0.3543 9.0000 ~34 0.750 8.two mm
M9x1 0.3543 9.0000 ~26 1.000 8 mm
M9x1.25 0.3543 9.0000 ~21 1.250 7.8 mm
3/8-24 0.3750 ix.5250 24 1.058 Q
3/8-16 0.3750 9.5250 16 1.588 5/sixteen in
M10x0.75 0.3937 10.0000 ~34 0.750 nine.ii mm
M10x1.v 0.3937 x.0000 ~17 one.500 8.5 mm
M10x1.25 0.3937 10.0000 ~21 ane.250 8.8 mm
M10x1 0.3937 10.0000 ~26 i.000 9 mm
M11x0.75 0.4331 11.0000 ~34 0.750 ten.2 mm
M11x1 0.4331 11.0000 ~26 1.000 x mm
M11x1.5 0.4331 11.0000 ~17 i.500 nine.5 mm
7/xvi-fourteen 0.4375 11.1125 14 ane.814 U
7/sixteen-20 0.4375 11.1125 20 1.270 25/64 in
M12x1.5 0.4724 12.0000 ~17 1.500 ten.5 mm
M12x1.75 0.4724 12.0000 ~xv one.750 10.2 mm
M12x0.75 0.4724 12.0000 ~34 0.750 11.25 mm
M12x1 0.4724 12.0000 ~26 1.000 11 mm
M12x1.25 0.4724 12.0000 ~21 1.250 10.viii mm
i/ii-20 0.5000 12.7000 20 1.270 29/64 in
1/2-13 0.5000 12.7000 thirteen 1.954 27/64 in
M14x1.5 0.5512 fourteen.0000 ~17 1.500 12.v mm
M14x1.25 0.5512 14.0000 ~21 i.250 12.8 mm
M14x1 0.5512 fourteen.0000 ~26 one.000 thirteen mm
M14x2 0.5512 14.0000 ~13 2.000 12 mm
9/16-18 0.5625 14.2875 18 ane.411 33/64 in
9/16-12 0.5625 14.2875 12 2.117 31/64 in
M15x1 0.5906 fifteen.0000 ~26 i.000 14 mm
M15x1.5 0.5906 15.0000 ~17 1.500 13.5 mm
five/8-18 0.6250 15.8750 18 1.411 37/64 in
5/8-11 0.6250 fifteen.8750 11 ii.309 17/32 in
M16x2 0.6299 16.0000 ~xiii 2.000 14 mm
M16x1.5 0.6299 16.0000 ~17 1.500 14.5 mm
M16x1 0.6299 16.0000 ~26 1.000 xv mm
M17x1 0.6693 17.0000 ~26 one.000 sixteen mm
M17x1.v 0.6693 17.0000 ~17 1.500 15.5 mm
M18x2.v 0.7087 xviii.0000 ~11 two.500 fifteen.five mm
M18x1 0.7087 xviii.0000 ~26 ane.000 17 mm
M18x1.5 0.7087 xviii.0000 ~17 1.500 sixteen.5 mm
M18x2 0.7087 eighteen.0000 ~13 two.000 sixteen mm
3/four-xvi 0.7500 19.0500 16 ane.588 eleven/16 in
3/iv-x 0.7500 19.0500 ten ii.540 21/32 in
M20x2 0.7874 20.0000 ~13 2.000 18 mm
M20x1.v 0.7874 twenty.0000 ~17 ane.500 18.5 mm
M20x1 0.7874 xx.0000 ~26 1.000 xix mm
M20x2.5 0.7874 20.0000 ~11 2.500 17.v mm
M22x2 0.8661 22.0000 ~thirteen ii.000 20 mm
M22x1.5 0.8661 22.0000 ~17 1.500 20.v mm
M22x1 0.8661 22.0000 ~26 i.000 21 mm
M22x2.five 0.8661 22.0000 ~11 2.500 19.v mm
7/8-9 0.8750 22.2250 9 2.822 49/64 in
vii/8-fourteen 0.8750 22.2250 14 1.814 13/16 in
M24x3 0.9449 24.0000 ~9 3.000 21 mm
M24x1 0.9449 24.0000 ~26 1.000 23 mm
M24x1.5 0.9449 24.0000 ~17 1.500 22.5 mm
M24x2 0.9449 24.0000 ~13 2.000 22 mm
M25x2 0.9843 25.0000 ~thirteen ii.000 23 mm
M25x1 0.9843 25.0000 ~26 i.000 24 mm
M25x1.5 0.9843 25.0000 ~17 1.500 23.5 mm
1-14 1.0000 25.4000 14 1.814 15/xvi in
1-8 ane.0000 25.4000 8 3.175 7/8 in
M26x1.5 i.0236 26.0000 ~17 one.500 24.5 mm
M27x1.5 1.0630 27.0000 ~17 1.500 25.5 mm
M27x3 1.0630 27.0000 ~9 3.000 24 mm
M27x1 1.0630 27.0000 ~26 1.000 26 mm
M27x2 one.0630 27.0000 ~13 2.000 25 mm
M28x2 ane.1024 28.0000 ~thirteen 2.000 26 mm
M28x1 1.1024 28.0000 ~26 1.000 27 mm
M28x1.five 1.1024 28.0000 ~17 1.500 26.5 mm
1 1/8-12 1.1250 28.5750 12 2.117 i 3/64 in
1 1/eight-seven 1.1250 28.5750 7 3.629 63/64 in
M30x1.5 1.1811 thirty.0000 ~17 one.500 28.v mm
M30x3.five one.1811 30.0000 ~8 3.500 26.5 mm
M30x2 1.1811 30.0000 ~13 2.000 28 mm
1 one/iv-12 ane.2500 31.7500 12 two.117 i xi/64 in
1 1/4-vii ane.2500 31.7500 7 three.629 1 seven/64 in
M33x2 1.2992 33.0000 ~13 two.000 31 mm
M33x3.5 1.2992 33.0000 ~8 3.500 29.5 mm
M36x3 one.4173 36.0000 ~9 iii.000 33 mm
M36x4 1.4173 36.0000 ~7 iv.000 32 mm
1 one/2 -12 ane.5000 38.thou 12 2.117 1 27/64 in
one 1/ii-half dozen one.5000 38.g vi 4.233 1 eleven/32 in
M39x4 i.5354 39.0000 ~7 iv.000 35 mm
M39x3 i.5354 39.0000 ~nine 3.000 36 mm
M42x4.5 i.6535 42.0000 ~half-dozen iv.500 37.five mm
ane iii/4-12 1.7500 44.4500 12 two.117 one 43/64 in
1 3/4-5 1.7500 44.4500 5 5.080 i 35/64 in
M45x4.five one.7717 45.0000 ~vi 4.500 40.5 mm
M48x5 i.8898 48.0000 ~vi 5.000 43 mm
2-12 2.0000 l.8000 12 ii.117 1 59/64 in
2-4 i/2 2.0000 50.8000 4.v 5.644 ane 25/32 in
M52x5 ii.0472 52.0000 ~six 5.000 47 mm
M56x5.v 2.2047 56.0000 ~5 5.500 50.five mm
M60x5.5 2.3622 60.0000 ~v 5.500 54.5 mm
M64x6 2.5197 64.0000 ~five 6.000 58 mm
M68x6 two.6772 68.0000 ~v 6.000 62 mm