Socket Size Chart: SAE to Metric Conversion | TaskHolt
Socket Size Chart (SAE to Metric)
A socket and wrench size chart pairing the closest SAE (inch) and metric (mm) sizes — handy when you have one set and need the other.
SAE to metric socket sizes (closest match)
| SAE (in) | Metric (mm) |
|---|---|
| 3/16 | 5 mm |
| 1/4 | 6-7 mm |
| 5/16 | 8 mm |
| 3/8 | 10 mm |
| 7/16 | 11 mm |
| 1/2 | 13 mm |
| 9/16 | 14 mm |
| 5/8 | 16 mm |
| 11/16 | 17-18 mm |
| 3/4 | 19 mm |
| 13/16 | 21 mm |
| 7/8 | 22 mm |
| 15/16 | 24 mm |
| 1 | 25-26 mm |
These are the nearest equivalents, not exact. Using a slightly oversized socket can round off a fastener — always use the correct size where possible, especially on tight or soft bolts.
Frequently asked questions
Is a 3/8 socket the same as 10mm?
Almost — 3/8 in is 9.53 mm, so a 10 mm is the closest metric size, but they are not identical. Use the exact size when you can.
What metric size is closest to 1/2 inch?
13 mm is the closest metric socket to 1/2 in (12.7 mm).