METRIC THREAD - Drill & Tap Chart (ISO)

Lookup table of the corresponding borehole diameter for tarting and ISO standard pitch lookup to determine the common thread steps for each taro size and to determine the hole to be drilled before tapping, applicable to taro. hand or tart with a specialized tapping machine.

Course Thread Sizes
Tap (Thread) Size	Drill Size(mm)
M4 x 0.35	3.60
M4 x 0.5	3.50
M5 x 0.5	4.50
M6 x .5	5.50
M6 x .75	5.25
M7 x .75	6.25
M8 x .5	7.50
M8 x .75	7.25
M8 x 1	7.00
M9 x 1	8.00
M10 x 0.75	9.25
M10 x 1	9.0
M10 x 1.25	8.8
M11 x 1	10.0
M12 x .75	11.25
M12 x 1	11.0
M12 x 1.5	10.5
M14 x 1	13.0
M14 x 1.25	12.8
M14 x 1.5	12.5
M16 x 1	15.0
M16 x 1.5	15.0
M18 x 1	17.0
M18 x 2	16.0
M20 x 1	19.0
M20 x 1.5	18.5
M20 x 2	18.0
M22 x 1	21.0
M22 x 1.5	20.5
M22 x 2	20.0
M24 x 1.5	22.5
M24 x 2	22.0
M26 x 1.5	24.5
M27 x 1.5	25.5
M27 x 2	25.0
M28 x 1.5	26.5
M30 x 1.5	28.5
M30 x 2	28.0
M33 x 2	31.0
M36 x 3	33.0

Fine Thread Sizes
Tap (Thread) Size	Drill Size(mm)
M1 x 0.25	0.75
M1.1 x 0.25	0.85
M1.2 x 0.25	0.95
M1.4 x 0.3	1.10
M1.6 x 0.35	1.25
M1.8 x 0.35	1.45
M2 x 0.4	1.60
M2.2 x 0.45	1.75
M2.5 x 0.45	2.05
M3 x 0.5	2.50
M3.5 x 0.6	2.90
M4 x 0.7	3.30
M4.5 x 0.75	3.70
M5 x 0.8	4.20
M6 x 1	5.00
M7 x 1	6.00
M8 x 1.25	6.80
M9 x 1.25	7.80
M10 x 1.5	8.50
M11 x 1.5	9.50
M12 x 1.75	10.25
M14 x 2	12.00
M16 x 2	14.00
M18 x 2.5	15.50
M20 x 2.5	17.50
M22 x 2.5	19.50
M24 x 3	21.00
M27 x 3	24.00
M30 x 3.5	26.50
M33 x 3.5	29.50
M36 x 4	32.00
M39 x 4	35.00
M42 x 4.5	37.50
M45 x 4.5	40.50
M48 x 5	43.00
M52 x 5	47.00
M56 x 5.5	50.50
M60 x 5.5	54.50
M64 x 6	58.00
M68 x 6	62.00

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