24 mm spanner
24.00 mm · 0.94 in
24 mm across the flats · fits a M16 hex head
The nearest imperial size
15/16″ is 23.81 mm — 0.19 mm smaller than 24 mm.
0.19 mm is a marginal fit: usable on a fastener that turns freely, and a poor idea on one that is seized or soft.
The numbers
| Across flats | 24.00 mm · 0.94 in |
| Nearest imperial | 15/16″ — 23.81 mm |
| Difference | 0.19 mm — marginal |
| Fits | M16 hex head |
Nearby metric sizes
| Size | mm | Nearest imperial | Gap |
|---|---|---|---|
| 21 mm | 21.00 | 13/16″ | 0.36 mm — do not |
| 22 mm | 22.00 | 7/8″ | 0.22 mm |
| 24 mm | 24.00 | 15/16″ | 0.19 mm |
| 27 mm | 27.00 | 1-1/16″ | 0.01 mm — swap |
Frequently asked questions
What is 24 mm in inches?
0.94 inches. The nearest imperial spanner is 15/16″ at 23.81 mm, 0.19 mm smaller.
Can I use 15/16″ instead of 24 mm?
Marginally. 0.19 mm is enough to feel loose on a tight fastener and enough to round a soft one. It will work on something that is not seized; it is not what you want on something that is.
What bolt does a 24 mm spanner fit?
A M16 hex head. The full metric thread chart gives the tapping drill and clearance hole for it too.