# INTERNAL METRIC THREAD DIMENSIONS CHART

Metric thread dimensions chart for internal threads according to ASME B1.13M-2005 "Metric Screw Threads: M Profile" standard. Dimensions of minor diameter, pitch diameter and major diameter for M profile metric internal threads are given in the chart. All dimensions are in millimeters.

Internal thread (or nut thread) is a term to describe all internal threads in ISO metric thread standards.

Threads produced to ASME B1.13M-2005 standard are fully interchangeable with threads that are based on ISO 68-1 basic profile and ISO 965-1 tolerance practices.

Selected Internal Thread Tolerance Classes:

-No-allowance - tolerance class 6H.

Internal threads with allowance are not standard practice.

Standard internal threads provide no allowance for coating thickness. Use the allowance provided by tolerance position G if 4 times the maximum coating thickness specified is equal or less than this allowance. Check ASME B1.13M - 2005 standard for more information.

The designation of a screw thread gives the thread symbol, the nominal size, the pitch, and the thread tolerance class (Ex: M6 x 1 - 5H6H). In internal thread tolerance class designation, the pitch diameter tolerance is followed by minor diameter tolerance. If the two class designations for the pitch diameter and minor diameter are same, it is not necessary to repeat the symbols. (Ex: M6 x 1 - 6H)

### Internal Metric Thread Calculator:

 INPUT PARAMETERS Thread Designation M1.6 x 0.35 M2 x 0.4 M2.5 x 0.45 M3 x 0.5 M3.5 x 0.6 M4 x 0.7 M5 x 0.8 M6 x 1 M8 x 1.25 M8 x 1 M10 x 1.5 M10 x 1.25 M10 x 1 M10 x 0.75 M12 x 1.75 M12 x 1.5 M12 x 1.25 M12 x 1 M14 x 2 M14 x 1.5 M15 x 1 M16 x 2 M16 x 1.5 M17 x 1 M18 x 1.5  M20 x 2.5 M20 x 1.5 M20 x 1 M22 x 2.5 M22 x 1.5 M24 x 3 M24 x 2 M25 x 1.5 M27 x 3 M27 x 2 M30 x 3.5 M30 x 2 M30 x 1.5 M33 x 2 M35 x 1.5 M36 x 4 M36 x 2 M39 x 2 M40 x 1.5 M42 x 4.5 M42 x 2 M45 x 1.5 M48 x 5 M48 x 2 M50 x 1.5 M55 x 1.5 M56 x 5.5 M56 x 2 M60 x 1.5 M64 x 6 M64 x 2 M65 x 1.5 M70 x 1.5 M72 x 6 M72 x 2 M75 x 1.5 M80 x 6 M80 x 2 M80 x 1.5 M85 x 2 M90 x 6 M90 x 2 M95 x 2 M100 x 6 M100 x 2 M105 x 2 M110 x 2 M120 x 2 M130 x 2 M140 x 2 M150 x 2 M160 x 3 M170 x 3 M180 x 3 M190 x 3 M200 x 3 RESULTS Thread Designation --- Pitch, p --- Tolerance Class --- Minor Diameter D1min --- D1max --- Pitch Diameter D2min --- D2max --- Major Diameter Dmin --- Dmax ---

General Note: All dimensions are in millimeters.

### Metric Thread Chart:

 Internal Metric Thread Chart — Limiting Dimensions for M Profile Thread Designation Pitch, p Tolerance Class Minor Dia., D1 Pitch Dia., D2 Major Dia., D min. max. min. max. min. max. (Note 1) M1.6 x 0.35 0.35 6H 1.221 1.321 1.373 1.458 1.600 1.736 M2 x 0.4 0.4 6H 1.567 1.679 1.740 1.830 2.000 2.148 M2.5 x 0.45 0.45 6H 2.013 2.138 2.208 2.303 2.500 2.660 M3 x 0.5 0.5 6H 2.459 2.599 2.675 2.775 3.000 3.172 M3.5 x 0.6 0.6 6H 2.850 3.010 3.110 3.222 3.500 3.698 M4 x 0.7 0.7 6H 3.242 3.422 3.545 3.663 4.000 4.219 M5 x 0.8 0.8 6H 4.134 4.334 4.480 4.605 5.000 5.240 M6 x 1 1 6H 4.917 5.153 5.350 5.500 6.000 6.294 M8 x 1.25 1.25 6H 6.647 6.912 7.188 7.348 8.000 8.340 M8 x 1 1 6H 6.917 7.153 7.350 7.500 8.000 8.294 M10 x 1.5 1.5 6H 8.376 8.676 9.026 9.206 10.000 10.397 M10 x 1.25 1.25 6H 8.647 8.912 9.188 9.348 10.000 10.340 M10 x 1 1 6H 8.917 9.153 9.350 9.500 10.000 10.294 M10 x 0.75 0.75 6H 9.188 9.378 9.513 9.645 10.000 10.240 M12 x 1.75 1.75 6H 10.106 10.441 10.863 11.063 12.000 12.452 M12 x 1.5 1.5 6H 10.376 10.676 11.026 11.216 12.000 12.407 M12 x 1.25 1.25 6H 10.647 10.912 11.188 11.368 12.000 12.360 M12 x 1 1 6H 10.917 11.153 11.350 11.510 12.000 12.304 M14 x 2 2 6H 11.835 12.210 12.701 12.913 14.000 14.501 M14 x 1.5 1.5 6H 12.376 12.676 13.026 13.216 14.000 14.407 M15 x 1 1 6H 13.917 14.153 14.350 14.510 15.000 15.304 M16 x 2 2 6H 13.835 14.210 14.701 14.913 16.000 16.501 M16 x 1.5 1.5 6H 14.376 14.676 15.026 15.216 16.000 16.407 M17 x 1 1 6H 15.917 16.153 16.350 16.510 17.000 17.304 M18 x 1.5 1.5 6H 16.376 16.676 17.026 17.216 18.000 18.407 M20 x 2.5 2.5 6H 17.294 17.744 18.376 18.600 20.000 20.585 M20 x 1.5 1.5 6H 18.376 18.676 19.026 19.216 20.000 20.407 M20 x 1 1 6H 18.917 19.153 19.350 19.510 20.000 20.304 M22 x 2.5 2.5 6H 19.294 19.744 20.376 20.600 22.000 22.585 M22 x 1.5 1.5 6H 20.376 20.676 21.026 21.216 22.000 22.407 M24 x 3 3 6H 20.752 21.252 22.051 22.316 24.000 24.698 M24 x 2 2 6H 21.835 22.210 22.701 22.925 24.000 24.513 M25 x 1.5 1.5 6H 23.376 23.676 24.026 24.226 25.000 25.417 M27 x 3 3 6H 23.752 24.252 25.051 25.316 27.000 27.698 M27 x 2 2 6H 24.835 25.210 25.701 25.925 27.000 27.513 M30 x 3.5 3.5 6H 26.211 26.771 27.727 28.007 30.000 30.786 M30 x 2 2 6H 27.835 28.210 28.701 28.925 30.000 30.513 M30 x 1.5 1.5 6H 28.376 28.676 29.026 29.226 30.000 30.417 M33 x 2 2 6H 30.835 31.210 31.701 31.925 33.000 33.513 M35 x 1.5 1.5 6H 33.376 33.676 34.026 34.226 35.000 35.417 M36 x 4 4 6H 31.670 32.270 33.402 33.702 36.000 36.877 M36 x 2 2 6H 33.835 34.210 34.701 34.925 36.000 36.513 M39 x 2 2 6H 36.835 37.210 37.701 37.925 39.000 39.513 M40 x 1.5 1.5 6H 38.376 38.676 39.026 39.226 40.000 40.417 M42 x 4.5 4.5 6H 37.129 37.799 39.077 39.392 42.000 42.964 M42 x 2 2 6H 39.835 40.210 40.701 40.925 42.000 42.513 M45 x 1.5 1.5 6H 43.376 43.676 44.026 44.226 45.000 45.417 M48 x 5 5 6H 42.587 43.297 44.752 45.087 48.000 49.056 M48 x 2 2 6H 45.835 46.210 46.701 46.937 48.000 48.525 M50 x 1.5 1.5 6H 48.376 48.676 49.026 49.238 50.000 50.429 M55 x 1.5 1.5 6H 53.376 53.676 54.026 54.238 55.000 55.429 M56 x 5.5 5.5 6H 50.046 50.796 52.428 52.783 56.000 57.149 M56 x 2 2 6H 53.835 54.210 54.701 54.937 56.000 56.525 M60 x 1.5 1.5 6H 58.376 58.676 59.026 59.238 60.000 60.429 M64 x 6 6 6H 57.505 58.305 60.103 60.478 64.000 65.241 M64 x 2 2 6H 61.835 62.210 62.701 62.937 64.000 64.525 M65 x 1.5 1.5 6H 63.376 63.676 64.026 64.238 65.000 65.429 M70 x 1.5 1.5 6H 68.376 68.676 69.026 69.238 70.000 70.429 M72 x 6 6 6H 65.505 66.305 68.103 68.478 72.000 73.241 M72 x 2 2 6H 69.835 70.210 70.701 70.937 72.000 72.525 M75 x 1.5 1.5 6H 73.376 73.676 74.026 74.238 75.000 75.429 M80 x 6 6 6H 73.505 74.305 76.103 76.478 80.000 81.241 M80 x 2 2 6H 77.835 78.210 78.701 78.937 80.000 80.525 M80 x 1.5 1.5 6H 78.376 78.676 79.026 79.238 80.000 80.429 M85 x 2 2 6H 82.835 83.210 83.701 83.937 85.000 85.525 M90 x 6 6 6H 83.505 84.305 86.103 86.478 90.000 91.241 M90 x 2 2 6H 87.835 88.210 88.701 88.937 90.000 90.525 M95 x 2 2 6H 92.835 93.210 93.701 93.951 95.000 95.539 M100 x 6 6 6H 93.505 94.305 96.103 96.503 100.000 101.266 M100 x 2 2 6H 97.835 98.210 98.701 98.951 100.000 100.539 M105 x 2 2 6H 102.835 103.210 103.701 103.951 105.000 105.539 M110 x 2 2 6H 107.835 108.210 108.701 108.951 110.000 110.539 M120 x 2 2 6H 117.835 118.210 118.701 118.951 120.000 120.539 M130 x 2 2 6H 127.835 128.210 128.701 128.951 130.000 130.539 M140 x 2 2 6H 137.835 138.210 138.701 138.951 140.000 140.539 M150 x 2 2 6H 147.835 148.210 148.701 148.951 150.000 150.539 M160 x 3 3 6H 156.752 157.252 158.051 158.351 160.000 160.733 M170 x 3 3 6H 166.752 167.252 168.051 168.351 170.000 170.733 M180 x 3 3 6H 176.752 177.252 178.051 178.351 180.000 180.733 M190 x 3 3 6H 186.752 187.252 188.051 188.386 190.000 190.768 M200 x 3 3 6H 196.752 197.252 198.051 198.386 200.000 200.768

General Note: All dimensions are in millimeters.

Note 1: Dimension is used in the design of tools, etc. In dimensioning internal threads it is not normally specified.

### Supplements:

 Link Usage ISO metric screw thread calculator ISO metric screw thread calculator based on ISO standards External Metric Thread Chart External metric thread chart according to ASME B1.13M-2005 standard.

### Definitions:

Allowance: The difference between the maximum material size and the basic size.

Basic profile: The theoretical profile of a screw thread in an axial plane defined by theoretical dimensions and angles common to internal and external threads. The basic M thread profile for metric screw threads is shown below.

ISO metric screw thread basic profile according to ISO 68-1

### Reference:

• ASME B1.13M-2005 "Metric Screw Threads: M Profile"
• Oberg, E. , Jones ,F.D. , Horton H.L. , Ryffel H.H., (2016) . Machinery's Handbook . 30th edition.  Industrial Press Inc.
• Oberg, E. , Jones ,F.D. , Horton H.L. , Ryffel H.H., (2012) . Machinery's Handbook . 29th edition.  Industrial Press Inc.