A23 battery size
10.3 × 28.5 mm
12 V · Alkaline · Cylindrical · also sold as 8LR932, MN21, V23GA
About the A23
The narrow 12 V cell in car key fobs and garage remotes. Like the 9V it is a stack — eight small alkaline cells in series — which is why a 12 V battery this small exists at all and why its capacity is tiny.
The numbers
| Diameter | 10.3 mm · 0.41 in |
| Height | 28.5 mm · 1.12 in |
| Nominal voltage | 12 V |
| Chemistry | Alkaline |
| Other names | 8LR932, MN21, V23GA |
Same diameter, different length
These are the cells most often confused with a A23, because they are exactly as wide and only differ in one dimension.
| Cell | Diameter | Length | vs A23 |
|---|---|---|---|
| AAA | 10.5 mm | 44.5 mm | +16.0 mm |
Other cylindrical sizes
| Cell | Size | Voltage |
|---|---|---|
| AAA | 10.5 × 44.5 mm | 1.5 V |
| AA | 14.5 × 50.5 mm | 1.5 V |
| C | 26.2 × 50 mm | 1.5 V |
| D | 34.2 × 61.5 mm | 1.5 V |
| AAAA | 8.3 × 42.5 mm | 1.5 V |
| N | 12 × 30.2 mm | 1.5 V |
| CR123A | 17 × 34.5 mm | 3 V |
| 18650 | 18 × 65 mm | 3.7 V |
| 21700 | 21 × 70 mm | 3.7 V |
Frequently asked questions
What size is a A23 battery?
10.3 mm across and 28.5 mm long — 0.41 × 1.12 inches.
What voltage is a A23?
12 V (Alkaline).
What is another name for a A23?
8LR932, MN21, V23GA — all the same cell.
Can I use a AAA instead of a A23?
They are the same diameter, 10.3 mm, and different lengths: 28.5 mm against 44.5. A AAA is thicker and often will not let the compartment close. Same voltage, so nothing is damaged by trying.