Battery Size Chart (AA, AAA, C, D, 9V, CR123A)
Physical dimensions and nominal voltage for the common consumer battery sizes, with their IEC designations.
| Common name | IEC designation | Shape | Length (mm) | Diameter (mm) | Nominal V |
|---|
Standard: IEC 60086, ANSI C18 · Data checked: 2026-10-14
Frequently asked questions
Are AA alkaline, NiMH and lithium cells interchangeable?
Physically yes, electrically no. Alkaline and lithium AA are 1.5 V nominal, NiMH is 1.2 V. Devices that are voltage-sensitive may underperform on NiMH; devices that draw high current may drain alkaline very quickly, where NiMH does better. Check the datasheet if it matters.
Why is a protected 18650 longer than the nominal 65 mm?
The protection circuit and the button top sit on top of the bare cell, so a protected 18650 is typically 68 to 70 mm long rather than 65 mm. A holder sized for the bare cell will not close on a protected one. Always check the datasheet dimension, not the nominal name.
What do the numbers in CR2032 mean?
Diameter and thickness: 20 mm across and 3.2 mm thick. The prefix tells you the chemistry — CR is lithium manganese dioxide, LR is alkaline. That is why a CR2032 and an LR44 are not interchangeable even though both are button cells.
What is the IEC designation for?
It is the international name for the same cell, so a cell can be listed under several national part numbers. US AA is LR6 under IEC, MN1500 under Duracell and E91 under Energizer — all the same physical size.