Introduction to Socket Conversion
A user-friendly socket size conversion guide makes switching between metric and standard sockets a breeze. Use this chart to simplify your socket conversions and streamline your tool selection.
Conversion Guide
Socket Conversion Chart
Use the red chart for Metric to Standard conversions and the blue chart for Standard to Metric conversions.
Each chart provides the closest larger common socket for optimal fit; using a smaller socket may not fit your bolt.
From Metric | To SAE |
---|---|
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 3/8″ |
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" |
From SAE | To Metric |
---|---|
1/16" | 2 mm |
1/8" | 4 mm |
3/16" | 5 mm |
1/4" | 7 mm |
5/16" | 8 mm |
3/8" | 10 mm |
7/16" | 12 mm |
1/2" | 13 mm |
9/16" | 15 mm |
5/8" | 16 mm |
11/16" | 18 mm |
3/4" | 20 mm |
13/16" | 21 mm |
7/8" | 23 mm |
15/16" | 24 mm |
1" | 26 mm |
1 1/16" | 27 mm |
1 1/8" | 29 mm |
1 3/16" | 31 mm |
1 1/4" | 32 mm |
1 5/16" | 34 mm |
1 3/8" | 35 mm |
1 7/16" | 37 mm |
1 1/2" | 39 mm |
1 9/16" | 40 mm |
1 5/8" | 42 mm |
1 11/16" | 43 mm |
1 3/4" | 45 mm |
1 13/16" | 47 mm |
1 7/8" | 48 mm |
1 15/16" | 50 mm |
2″ | 51 mm |
Socket Chart Instructions

Use the RED socket size conversion chart to convert sockets from Metric(mm).
Use the BLUE socket size conversion chart to convert sockets from Standard(SAE).
Find your socket size on the left, and the nearest larger size in the other system is on the right.
MM to inch and inch to mm charts vary slightly. The converted socket should be a bit larger than the fastener for a proper fit. If a socket is smaller than the bolt you want to use it on, it won't fit.
There is no exact match between sockets of different measurement systems.
MM Socket to Standard
If you know the millimeter measurement of your socket and require information on its equivalent size in inches:
- 4mm Socket: 5/32" (0.1575 inches)
- 5mm Socket: 7/32″ (0.1969 inches)
- 6mm Socket: 1/4″ (0.2362 inches)
- 7mm Socket: 9/32″ (0.2756 inches)
- 8mm Socket: 11/32″ (0.3150 inches)
- 9mm Socket: 3/8″ (0.3543 inches)
- 10mm Socket: 13/32″ (0.3937 inches)
- 11mm Socket: 7/16″ (0.4331 inches)
- 12mm Socket: 1/2″ (0.4724 inches)
- 13mm Socket: 17/32″ (0.5118 inches)
- 14mm Socket: 9/16″ (0.5512 inches)
- 15mm Socket: 19/32″ (0.5906 inches)
- 16mm Socket: 21/32" (0.6299 inches)
- 17mm Socket: 11/16″ (0.6693 inches)
- 18mm Socket: 23/32″ (0.7087 inches)
- 19mm Socket: 3/4″ (0.7480 inches)
- 20mm Socket: 13/16″ (0.7874 inches)
- 21mm Socket: 27/32″ (0.8268 inches)
- 22mm Socket: 7/8″ (0.8661 inches)
- 23mm Socket: 29/32″(0.9055 inches)
- 24mm Socket: 31/32″ (0.9449 inches)
- 25mm Socket: 1″ (0.9843 inches)
- 26mm Socket: 1 1/32″ (1.0236 inches)
- 27mm Socket: 1 1/16″ (1.0630 inches)
- 28mm Socket: 1 1/8″ (1.1024 inches)
- 29mm Socket: 1 5/32″ (1.1417 inches)
- 30mm Socket: 1 3/16″ (1.1811 inches)
- 31mm Socket: 1 7/32″ (1.2205 inches)
- 32mm Socket: 1 3/8″ (1.2598 inches)
- 33mm Socket: 1 5/16″ (1.2992 inches)
- 34mm Socket: 1 11/32″ (1.3386 inches)
- 35mm Socket: 1 3/8″ (1.3780 inches)
- 36mm Socket: 1 7/16″ (1.4173 inches)
- 37mm Socket: 1 15/32″ (1.4567 inches)
- 38mm Socket: 1 1/2″ (1.4961 inches)
- 39mm Socket: 1 9/16″ (1.5354 inches)
- 40mm Socket: 1 19/32″ (1.5748 inches)
- 41mm Socket: 1 5/8″ (1.6142 inches)
- 42mm Socket: 1 21/32″ (1.6535 inches)
- 43mm Socket: 1 23/32″ (1.6929 inches)
- 44mm Socket: 1 3/4″ (1.7323 inches)
- 45mm Socket: 1 25/32″ (1.7717 inches)
- 46mm Socket: 1 13/16″(1.8110 inches)
- 47mm Socket: 1 7/8″ (1.8504 inches)
- 48mm Socket: 1 29/32″ (1.8898 inches)
- 49mm Socket: 1 15/16″ (1.9291 inches)
- 50mm Socket: 1 31/32" (1.9685 inches)
Test the Socket Conversion
After you've completed the conversion process, give the converted socket a try! Attach it to your wrench, gently tighten a bolt, and see how it feels.
If you think it feels too loose, trust your instincts. Applying pressure on a loose socket can cause damage and injury.
Quick Tip: If it feels a bit loose, try covering the bolt with a shop cloth before attaching the socket. Keep in mind, this works best with lighter torque.
Ensure that the socket securely grips the fastener without slipping, and verify that it doesn't round off the edges.
Common Conversions
These are some of the more common socket conversion requests:
36mm Socket to Standard
- A 36mm socket is approximately equivalent to a 1 1/2 inch socket.
- While a 1 7/16" socket might be a better fit, it's less commonly available in store-bought socket sets.
30mm Socket to Standard
- A 30mm socket is roughly equivalent to a 1-1/4 inch socket.
- This size is commonly used for various automotive tasks.
1 1/8" Socket to MM
- The closest metric socket size for a 1 1/8 inch bolt is typically a 30mm socket.
- Some sets may include a 29mm socket for a better fit.
1 7/16" Socket to MM
- A 1 7/16" socket is roughly equivalent to a 38mm socket in the metric system.
- Specialty sockets like 1 7/16" are not commonly found in standard sets.
Remember: These are not exact measurements, they are rounded to the nearest socket size that will fit nuts and bolts.
Also: Use the Inch-lbs to Foot-lbs guide for help with torque wrench sockets and settings.
For easy reference, consider printing and storing a copy of this chart with your sockets.
Chart Download
You can download our Inches to Metric Conversion Chart(pdf) and get all exact Standard and Metric conversion measurements on your device.