Metric to Imperial Size Chart for Automotive - Common sizes

Metric to Imperial Conversion Chart

Metric to Imperial Conversion Chart

Metric (mm)	Imperial (inches)
1 mm	1/16 in
2 mm	1/16 in
3 mm	1/8 in
4 mm	3/16 in
5 mm	3/16 in
6 mm	1/4 in
7 mm	1/4 in
8 mm	5/16 in
9 mm	3/8 in
10 mm	3/8 in
11 mm	7/16 in
12 mm	1/2 in
13 mm	1/2 in
14 mm	9/16 in
15 mm	9/16 in
16 mm	5/8 in
17 mm	11/16 in
18 mm	11/16 in
19 mm	3/4 in
20 mm	13/16 in
21 mm	13/16 in
22 mm	7/8 in
23 mm	7/8 in
24 mm	15/16 in
25 mm	1 in
26 mm	1 in
27 mm	1 1/8 in
28 mm	1 1/8 in
29 mm	1 1/8 in
30 mm	1 1/8 in
31 mm	1 1/4 in
32 mm	1 1/4 in
33 mm	1 1/4 in
34 mm	1 3/8 in
35 mm	1 3/8 in
36 mm	1 3/8 in
37 mm	1 1/2 in
38 mm	1 1/2 in
39 mm	1 1/2 in
40 mm	1 5/8 in
41 mm	1 5/8 in
42 mm	1 5/8 in
43 mm	1 3/4 in
44 mm	1 3/4 in
45 mm	1 3/4 in
46 mm	1 3/4 in
47 mm	1 7/8 in
48 mm	1 7/8 in
49 mm	1 7/8 in
50 mm	2 in
51 mm	2 in
52 mm	2 in
53 mm	2 1/8 in
54 mm	2 1/8 in
55 mm	2 1/8 in
56 mm	2 1/4 in
57 mm	2 1/4 in
58 mm	2 1/4 in
59 mm	2 3/8 in
60 mm	2 3/8 in
61 mm	2 3/8 in
62 mm	2 1/2 in
63 mm	2 1/2 in
64 mm	2 1/2 in
65 mm	2 1/2 in
66 mm	2 5/8 in
67 mm	2 5/8 in
68 mm	2 5/8 in
69 mm	2 3/4 in
70 mm	2 3/4 in
71 mm	2 3/4 in
72 mm	2 7/8 in
73 mm	2 7/8 in
74 mm	2 7/8 in
75 mm	3 in
76 mm	3 in
77 mm	3 in
78 mm	3 1/8 in
79 mm	3 1/8 in
80 mm	3 1/8 in
81 mm	3 1/4 in
82 mm	3 1/4 in
83 mm	3 1/4 in
84 mm	3 1/4 in
85 mm	3 3/8 in
86 mm	3 3/8 in
87 mm	3 3/8 in
88 mm	3 1/2 in
89 mm	3 1/2 in
90 mm	3 1/2 in
91 mm	3 5/8 in
92 mm	3 5/8 in
93 mm	3 5/8 in
94 mm	3 3/4 in
95 mm	3 3/4 in
96 mm	3 3/4 in
97 mm	3 7/8 in
98 mm	3 7/8 in
99 mm	3 7/8 in
100 mm	3 7/8 in
101 mm	4 in
102 mm	4 in
103 mm	4 in
104 mm	4 1/8 in
105 mm	4 1/8 in
106 mm	4 1/8 in
107 mm	4 1/4 in
108 mm	4 1/4 in
109 mm	4 1/4 in
110 mm	4 3/8 in
111 mm	4 3/8 in
112 mm	4 3/8 in
113 mm	4 1/2 in
114 mm	4 1/2 in
115 mm	4 1/2 in
116 mm	4 5/8 in
117 mm	4 5/8 in
118 mm	4 5/8 in
119 mm	4 5/8 in
120 mm	4 3/4 in
121 mm	4 3/4 in
122 mm	4 3/4 in
123 mm	4 7/8 in
124 mm	4 7/8 in
125 mm	4 7/8 in
126 mm	5 in
127 mm	5 in
128 mm	5 in
129 mm	5 1/8 in
130 mm	5 1/8 in

 

Understanding Metric and Imperial Measurements for Automotive Piping Sizes

In the automotive world, finding the right piping can be a challenge, especially when different manufacturers use different measurement systems. Some manufacturers adhere to metric sizing, while others use imperial. This can create confusion when you’re looking for specific parts, especially if you’re dealing with pipes, tubing, or other components that have precise size requirements.

Why the Difference?

The metric system, which measures in millimeters (mm), is more commonly used in Europe and many parts of Asia, while the imperial system, using inches, is more common in the United States and the UK. As automotive parts are manufactured globally, it’s essential to understand both systems to ensure you’re ordering the correct size.

Common Automotive Piping Sizes

For car enthusiasts, mechanics, or anyone dealing with exhaust systems, fuel lines, or custom builds, navigating these measurement systems can be tricky. For example, you may see an exhaust pipe listed as 50mm, while another brand might list it as 2 inches. Understanding that 50mm and 2 inches are nearly the same size can save you a lot of trouble when searching for parts or making modifications.

Helping You Find the Right Fit

To make your search easier, we’ve created a handy conversion chart that lists common automotive piping sizes in both metric and imperial units. With this chart, you can quickly match up metric sizes with their imperial counterparts (rounded to the nearest common fraction), ensuring you always find the right size, no matter what system the manufacturer uses.

Our goal is to simplify the process and eliminate guesswork so you can get back to working on your vehicle.