Metric to Standard Socket Conversion Chart
Use the chart below to simplify your socket size conversions from Metric to Standard. Important Considerations:
Proper Fit: To ensure a good fit, a converted socket must be slightly larger than the bolt it is intended for. Converting to a smaller socket won't fit.
No Exact Matches: Metric and standard socket sizes do not have exact counterparts.
Socket Conversion Chart
Metric to Standard | Standard to Metric
| From Metric | To Standard Socket |
|---|---|
| 4 mm | 5/32" |
| 5 mm | 7/32″ |
| 6 mm | 1/4″ |
| 7 mm | 9/32″ |
| 8 mm | 11/32″ |
| 9 mm | 3/8″ |
| 10 mm | 13/32″ |
| 11 mm | 7/16″ |
| 12 mm | 1/2″ |
| 13 mm | 17/32″ |
| 14 mm | 9/16″ |
| 15 mm | 19/32″ |
| 16 mm | 21/32" |
| 17 mm | 11/16″ |
| 18 mm | 23/32″ |
| 19 mm | 3/4″ |
| 20 mm | 13/16″ |
| 21 mm | 27/32″ |
| 22 mm | 7/8″ |
| 23 mm | 29/32″ |
| 24 mm | 31/32″ |
| 25 mm | 1″ |
| 26 mm | 1 1/32″ |
| 27 mm | 1 1/16″ |
| 28 mm | 1 1/8″ |
| 29 mm | 1 5/32″ |
| 30 mm | 1 3/16″ |
| 31 mm | 1 7/32″ |
| 32 mm | 1 9/32″ |
| 33 mm | 1 5/16″ |
| 34 mm | 1 11/32″ |
| 35 mm | 1 3/8″ |
| 36 mm | 1 7/16″ |
| 37 mm | 1 15/32″ |
| 38 mm | 1 1/2″ |
| 39 mm | 1 9/16″ |
| 40 mm | 1 19/32″ |
| 41 mm | 1 5/8″ |
| 42 mm | 1 21/32″ |
| 43 mm | 1 23/32″ |
| 44 mm | 1 3/4″ |
| 45 mm | 1 25/32″ |
| 46 mm | 1 13/16″ |
| 47 mm | 1 7/8″ |
| 48 mm | 1 29/32″ |
| 49 mm | 1 15/16″ |
| 50 mm | 1 31/32" |
Conversion Formula
For common mm to inch socket conversions the formula is 25.4 mm per inch.
4mm Socket to Inches
4 ÷ 25.4 = 0.15748 inches. The closest Standard size is 5/32".
5mm Socket to Inches
5 ÷ 25.4 = 0.19685 inches. The closest Standard size is 7/32".
6mm Socket to Inches
6 ÷ 25.4 = 0.23622 inches. The closest Standard size is 1/4".
7mm Socket to Inches
7 ÷ 25.4 = 0.275591 inches. The closest Standard size is 9/32".
8mm Socket to Inches
8 ÷ 25.4 = 0.314961 inches. The closest Standard size is 11/32".
9mm Socket to Inches
9 ÷ 25.4 = 0.354331 inches. The closest Standard size is 3/8".
10mm Socket to Inches
10 ÷ 25.4 = 0.393701 inches. The closest Standard size is 13/32".
11mm Socket to Inches
11 ÷ 25.4 = 0.433071 inches. The closest Standard size is 7/16".
12mm Socket to Inches
12 ÷ 25.4 = 0.472441 inches. The closest Standard size is 1/2".
13mm Socket to Inches
13 ÷ 25.4 = 0.511811 inches. The closest Standard size is 17/32".
14mm Socket to Inches
14 ÷ 25.4 = 0.551181 inches. The closest Standard size is 9/16".
15mm Socket to Inches
15 ÷ 25.4 = 0.590551 inches. The closest Standard size is 19/32".
16mm Socket to Inches
16 ÷ 25.4 = 0.629921 inches. The closest Standard size is 21/32".
17mm Socket to Inches
17 ÷ 25.4 = 0.669291 inches. The closest Standard size is 11/16".
18mm Socket to Inches
18 ÷ 25.4 = 0.708661 inches. The closest Standard size is 23/32".
19mm Socket to Inches
19 ÷ 25.4 = 0.748031 inches. The closest Standard size is 3/4".
20mm Socket to Inches
20 ÷ 25.4 = 0.787402 inches. The closest Standard size is 13/16".
21mm Socket to Inches
21 ÷ 25.4 = 0.826772 inches. The closest Standard size is 27/32".
22mm Socket to Inches
22 ÷ 25.4 = 0.866142 inches. The closest Standard size is 7/8".
23mm Socket to Inches
23 ÷ 25.4 = 0.905512 inches. The closest Standard size is 29/32".
24mm Socket to Inches
24 ÷ 25.4 = 0.944882 inches. The closest Standard size is 31/32".
25mm Socket to Inches
25 ÷ 25.4 = 0.984252 inches. The closest Standard size is 1".
26mm Socket to Inches
26 ÷ 25.4 = 1.02362 inches. The closest Standard size is 1 1/32".
27mm Socket to Inches
27 ÷ 25.4 = 1.06299 inches. The closest Standard size is 1 1/16".
28mm Socket to Inches
28 ÷ 25.4 = 1.10236 inches. The closest Standard size is 1 1/8".
29mm Socket to Inches
29 ÷ 25.4 = 1.14173 inches. The closest Standard size is 1 5/32".
30mm Socket to Inches
30 ÷ 25.4 = 1.1811 inches. The closest Standard size is 1 3/16".
31mm Socket to Inches
31 ÷ 25.4 = 1.22047 inches. The closest Standard size is 1 7/32".
32mm Socket to Inches
32 ÷ 25.4 = 1.25984 inches. The closest Standard size is 1 9/32".
33mm Socket to Inches
33 ÷ 25.4 = 1.29921 inches. The closest Standard size is 1 5/16".
34mm Socket to Inches
34 ÷ 25.4 = 1.33858 inches. The closest Standard size is 1 11/32".
35mm Socket to Inches
35 ÷ 25.4 = 1.37795 inches. The closest Standard size is 1 3/8".
36mm Socket to Inches
36 ÷ 25.4 = 1.41732 inches. The closest Standard size is 1 7/16".
37mm Socket to Inches
37 ÷ 25.4 = 1.45669 inches. The closest Standard size is 1 15/32".
38mm Socket to Inches
38 ÷ 25.4 = 1.49606 inches. The closest Standard size is 1 1/2".
39mm Socket to Inches
39 ÷ 25.4 = 1.53543 inches. The closest Standard size is 1 9/16".
40mm Socket to Inches
40 ÷ 25.4 = 1.5748 inches. The closest Standard size is 1 19/32".
41mm Socket to Inches
41 ÷ 25.4 = 1.61417 inches. The closest Standard size is 1 5/8".
42mm Socket to Inches
42 ÷ 25.4 = 1.65354 inches. The closest Standard size is 1 21/32".
43mm Socket to Inches
43 ÷ 25.4 = 1.69291 inches. The closest Standard size is 1 23/32".
44mm Socket to Inches
44 ÷ 25.4 = 1.73228 inches. The closest Standard size is 1 3/4".
45mm Socket to Inches
45 ÷ 25.4 = 1.77165 inches. The closest Standard size is 1 25/32".
46mm Socket to Inches
46 ÷ 25.4 = 1.81102 inches. The closest Standard size is 1 13/16".
47mm Socket to Inches
47 ÷ 25.4 = 1.85039 inches. The closest Standard size is 1 7/8".
48mm Socket to Inches
48 ÷ 25.4 = 1.88976 inches. The closest Standard size is 1 29/32".
49mm Socket to Inches
49 ÷ 25.4 = 1.92913 inches. The closest Standard size is 1 15/16".
50mm Socket to Inches
50 ÷ 25.4 = 1.9685 inches. The closest Standard size is 1 31/32".
