which fits?

Which battery, which bag, what size, how many. Look it up, then buy the right one once.

Sheet 04 · Batteries

What battery is this?

The battery came out of something, the sleeve is torn or printed in an alphabet you don’t read, and the shop has forty kinds on the wall. You know it’s round and about as long as your thumb. That’s enough. Every size that matters was fixed by the IEC decades ago to the tenth of a millimetre, and a ruler held against the end will tell an AA from an AAA from the thing that looks like an AA and will wreck whatever you put it in.

Measure across the flat end, not the nipple, then end to end. Put the two numbers in. The sheet names the size, gives the code the makers print in small type (LR6 for an alkaline AA), the voltage, and the pack. If what you measured matches nothing, it says so, and says what it’s nearest to, because nearly fitting is how the wrong battery gets bought.

1Work it out

The battery
Shape

Across the end, not including the nipple.

End to end, nipple included.

AA

IEC LR6 alkaline, R6 zinc carbon, FR6 (FR14505) lithium, HR6 rechargeable, ANSI 15A. 14.5 mm across, 50.5 mm long, 1.5 V, alkaline, zinc carbon, lithium or NiMH. The drawer staple: remotes, toys, clocks, torches. A 14500 lithium-ion cell is this can at 3.7 V. If the sleeve says 14500 or 3.7 V, it is not an AA and does not go in an AA device.

From the maker’s own datasheet: Energizer E91 datasheet.

Get AA alkaline batteries, a pack of 20 on Amazon.co.ukor search Amazon.co.uk for “AA batteries 20 pack”

The sizes, smallest first

NameIECANSISize, mmVChemistrySource
LR44 Also sold as A76, AG13, L1154.LR44 alkaline; the SR44 (357) is the silver version, same size1166A11.6 × 5.41.5alkalinemaker
CR1216CR1216n/a12.5 × 1.63lithiummaker
CR1220CR12205012LC12.5 × 23lithiummaker
CR1225CR1225n/a12.5 × 2.53lithiummaker
CR1616CR1616n/a16 × 1.63lithiummaker
CR1620CR16205009LC16 × 23lithiummaker
CR1632CR1632n/a16 × 3.23lithiummaker
CR2016CR20165000LC20 × 1.63lithiummaker
CR2025CR20255003LC20 × 2.53lithiummaker
CR2032 Also sold as DL2032, ECR2032.CR20325004LC20 × 3.23lithiummaker
CR2320CR2320n/a23 × 23lithiummaker
CR2354CR2354n/a23 × 5.43lithiummaker
CR2430CR24305011LC24.5 × 33lithiummaker
CR2450CR24505029LC24.5 × 53lithiummaker
CR2477CR2477n/a24.5 × 7.73lithiummaker
CR3032CR3032n/a30 × 3.23lithiummaker
A27 Twelve volts in a thing the size of a short AAAA.8LR732 (Duracell prints it; Energizer prints none)n/a8 × 28.212alkaline, eight cells in a tubemaker
AAAALR8D425, also written LR6125A8.3 × 42.51.5alkalinemaker
A23 Also sold as MN21, 23A, V23GA, LRV08. Twelve volts, not 1.5.8LR932 (Duracell prints it; Energizer prints none)1181A10.3 × 28.512alkaline, eight cells in a tubemaker
AAALR03 alkaline, R03 zinc carbon, FR03 lithium, HR03 rechargeable24A10.5 × 44.51.5alkaline, zinc carbon, lithium or NiMHmaker
1/3N Also sold as 2L76 and DL1/3N: a third the length of an N.CR11108n/a11.6 × 10.83lithiummaker
N Also sold as MN9100, E90, Lady. Not an A23: that one is 12 V and a shade thinner.LR1 alkaline, R1 zinc carbon910A12 × 30.21.5alkalinemaker
4LR44 Also sold as A544, 476A, PX28A.4LR441414A13 × 25.26alkaline, four LR44 cells in a tubemaker
1/2 AA Half an AA’s length at twice its voltage. The 3.6 V ER14250 in the same can is a different chemistry.CR14250n/a14.5 × 253lithiummaker
AA A 14500 lithium-ion cell is this can at 3.7 V. If the sleeve says 14500 or 3.7 V, it is not an AA and does not go in an AA device.LR6 alkaline, R6 zinc carbon, FR6 (FR14505) lithium, HR6 rechargeable15A14.5 × 50.51.5alkaline, zinc carbon, lithium or NiMHmaker
CR2CR15H2705046LC15.6 × 273lithiummaker
CR123A Also sold as 123, DL123A, EL123.CR173455018LC17 × 34.53lithiummaker
18650 18.6 by 65.2 at most, says Molicel: a shade over the name. Protected cells with a button top run longer still.none: the number is the sizen/a18.6 × 65.23.6lithium-ion, rechargeablemaker
21700none: the number is the sizen/a21.55 × 70.153.6lithium-ion, rechargeablemaker
26650 Murata’s table gives rounded figures. A C-sized can at 3.2 V.none: the number is the sizen/a26 × 663.2lithium iron phosphate, rechargeablemaker
C As long as an AA, nearly twice as wide.LR14 alkaline, R14 zinc carbon, HR14 rechargeable14A26.2 × 501.5alkaline, zinc carbon or NiMHmaker
DLR20 alkaline, R20 zinc carbon, HR20 rechargeable13A34.2 × 61.51.5alkaline, zinc carbon or NiMHmaker
2CR5 Also sold as DL245, EL2CR5, 245.2CR55032LC17 × 34 × 456lithium, two cells side by sidemaker
CR-P2 Also sold as 223, DL223, EL223.CR-P25024LC19.5 × 35 × 366lithium, two cells side by sidemaker
9V Also called PP3. Two snap studs on top.6LR61 or 6LF22 alkaline, 6F22 zinc carbon, HR9V rechargeable1604A26.5 × 17.5 × 48.59alkaline, six cells in a boxmaker
6 V lantern Also sold as 996, PJ996, 908.4R25 zinc carbon; the alkaline one is 4LR25908D68.2 × 68.2 × 1156zinc carbon, four F cells in a boxmaker

36 sizes. Millimetres, the maximums from the makers’ datasheets (diameter by height; width by depth by height for the boxes). A real battery measures at or a shade under them. The IEC code is the one on the sleeve in small print, and it carries the chemistry in its letters: the makers print LR6 on an alkaline AA, R6 on a zinc carbon one, FR6 on a lithium and HR6 on a rechargeable, and CR on a 3 V lithium coin or cylinder.

2Three names for one battery

An alkaline AA is an AA on the packet, an LR6 in the small print, a 15A in America and a Mignon in Germany, and they are all the same can: 14.5 millimetres across and 50.5 long, at most. Energizer’s datasheet prints two of those names on one line, ‘ANSI-15A, IEC-LR6’, and that line is the key to the whole wall of batteries. The IEC code carries the chemistry in its letters. Energizer prints LR6 on its alkaline AA, R6 on the cheap zinc carbon one and FR6 on the lithium, and Duracell’s chart puts HR6 on the rechargeable. Same can, four sets of letters, four batteries. A number in front is a count of cells: a 6LR61 is six little LR61 cells in a box, which is the 9 volt; a 4LR44 is four LR44 button cells in a tube, 6 volts; a 4R25 is four fat zinc cells in a lantern battery with springs on top.

3The one that looks like an AA and isn’t

Lithium-ion cells are named by their size in millimetres with no letters at all. An 18650 is 18 across and 65 long, a 21700 is 21 by 70, and a 14500 is 14 by 50, which is an AA to the eye and 3.7 volts to the circuit, two and a half times what the torch or the toy was built for. Molicel’s datasheet gives its 18650 as 18.6 by 65.2 at most, a shade over the name, which is why a tight holder is tight. If the sleeve says 3.6 V or 3.7 V, or a five-figure number with no letters, it is not an AA whatever it looks like, and it goes in nothing that didn’t ask for it by that number. The same care the other way: a CR123A is a stubby 3 volt lithium, 17 by 34.5, and it is not a C, a half-AA or anything else it resembles in the drawer.

4Why the numbers are maximums

The standard fixes the biggest a cell may be, so that it always goes into the holder, and the makers print the maximum and the minimum: Energizer’s AA is 14.5 across at most and 13.5 at least, 50.5 long at most and 49.5 at least. A real one measures at or a little under the top figure, and the sheet matches to the top figure with room for a ruler held badly. Measure across the flat end, not the nipple; the nipple is the positive terminal and is counted in the length, not the width. The gaps between sizes are millimetres, not tenths, so a school ruler does. The one place to take care is the A23 against the N: 10.3 by 28.5 against 12 by 30.2, close enough to fool a glance and eight times apart in voltage, with the A23 in the doorbell push and the N in the old torch.

5Coins and buttons

A flat coin has its size in its name. A CR2032 is 20 millimetres across and 3.2 thick, a CR2450 is 24.5 by 5, a CR1620 is 16 by 2. The chart has the common ones; the coin cell sheet has the lot, with every name each one is sold under, because the same 20 by 3.2 lithium coin hangs on three hooks in the shop as a CR2032, a DL2032 and an ECR2032.

6Where to get it

Those links go to Amazon.co.uk and earn this site a commission if you buy. The price is the same either way, and nothing on this sheet changes because of it.

7Where the numbers come from

  1. E91 AA product datasheet, Energizer. ANSI-15A, IEC-LR6; 1.5 V alkaline; diameter 14.50 mm maximum, 13.50 minimum; height 50.50 maximum, 49.50 minimum (read 17 October 2026)
  2. E92 AAA product datasheet, Energizer. ANSI-24A, IEC-LR03; 10.50 by 44.50 mm maximum (read 17 October 2026)
  3. E96 AAAA product datasheet, Energizer. ANSI-25A, IEC-LR8D425, LR61; 8.3 by 42.5 mm maximum (read 17 October 2026)
  4. E93 C product datasheet, Energizer. ANSI-14A, IEC-LR14; 26.20 by 50.00 mm maximum (read 17 October 2026)
  5. E95 D product datasheet, Energizer. ANSI-13A, IEC-LR20; 34.20 by 61.50 mm maximum (read 17 October 2026)
  6. 522 9V product datasheet, Energizer. ANSI 1604A, IEC-6LF22 or 6LR61; 9.0 V; 17.50 by 26.50 by 48.50 mm maximum (read 17 October 2026)
  7. E90 N product datasheet, Energizer. ANSI-910A, IEC-LR1; 12.00 by 30.20 mm (read 17 October 2026)
  8. A23 miniature alkaline datasheet, Energizer. 12 V; 10.30 by 28.50 mm maximum (read 17 October 2026)
  9. A27 miniature alkaline datasheet, Energizer. 12.0 V; 8.00 by 28.20 mm maximum; no IEC designation printed (read 17 October 2026)
  10. A544 datasheet, Energizer. ANSI/NEDA-1414A, IEC-4LR44; 6.0 V; four LR44 cells in series; 13.00 by 25.20 mm maximum (read 17 October 2026)
  11. 123 (EL123AP) lithium photo datasheet, Energizer. ANSI-5018LC, IEC-CR17345; 3.0 V; 17.00 by 34.50 mm maximum (read 17 October 2026)
  12. Battery and charger technical information: the size list, Energizer. Every Energizer battery with its IEC and ANSI codes, diameter and height; the CR2 is CR15H270, 5046LC, 15.6 by 27.0 mm (read 17 October 2026)
  13. 2CR5 (EL2CR5) lithium photo datasheet, Energizer. ANSI-5032LC, IEC-2CR5; 6.0 V; 17.00 by 34.00 by 45.00 mm maximum (read 17 October 2026)
  14. 223 (EL223) lithium photo datasheet, Energizer. ANSI-5024LC, IEC-CR-P2; 6.0 V; 19.50 by 35.00 by 36.00 mm maximum (read 17 October 2026)
  15. 2L76 (1/3N) lithium photo datasheet, Energizer. IEC-CR11108; 3.0 V; 11.60 by 10.80 mm maximum (read 17 October 2026)
  16. Eveready 1209 6 V lantern datasheet, Energizer. ANSI-908D, IEC-4R25; four F cells in series; 68.2 by 68.2 by 115 mm; the alkaline 529 prints 908A (read 17 October 2026)
  17. CR2032 datasheet (and the CR2025, CR2016, CR2450, CR2430, CR1632, CR1620, CR1616 and CR1220 sheets alongside it), Energizer. Each prints its IEC designation, 3.0 V, and the diameter and height maximum and minimum: the CR2032 is 20.00 by 3.20 mm (read 17 October 2026)
  18. A76 miniature alkaline datasheet, Energizer. ANSI/NEDA 1166A, IEC-LR44; 1.5 V; 11.60 by 5.40 mm maximum; the 357/303 sheet gives the silver oxide SR44 the same size at 1.55 V (read 17 October 2026)
  19. Lithium coin cells, Varta. Diameter and height for every coin, 3 V: CR1216 12.5 by 1.6, CR1225 12.5 by 2.5, CR2320 23 by 2, CR2354 23 by 5.4, CR2477 24.5 by 7.7, CR3032 30 by 3.2 (read 17 October 2026)
  20. Longlife Power AA, and the Super Heavy Duty and Ultra Lithium AA pages beside it, Varta. Reference IEC LR6, diameter 14.5 mm, height 50.5 mm, 1.5 V; the zinc carbon page says IEC R6 and the lithium page FR14505, same sizes (read 17 October 2026)
  21. 2024 Duracell battery specs: cross-reference chart, Duracell. HR6, HR03, HR14, HR20 and HR9V for the rechargeables; MN21 is 8LR932 and A23, MN27 is 8LR732 and A27; 123 is CR17345; 1/3N is CR11108 (read 17 October 2026)
  22. Product data sheet of INR-18650-P28A, Molicel. Nominal 3.6 V; diameter 18.6 mm maximum, height 65.2 mm maximum (read 17 October 2026)
  23. Product data sheet of INR-21700-P45B, Molicel. Nominal 3.6 V; diameter 21.55 mm maximum, height 70.15 mm maximum (read 17 October 2026)
  24. Cylindrical type lithium ion secondary batteries, Murata. The 18650 rows at 18 by 65 mm and 3.6 V, the 21700 at 21 by 70, the US26650FTC1A at 26 by 66 and 3.2 V; the US14500V safety data sheet gives 3.7 V (read 17 October 2026)
  25. CR14250 lithium battery, GP Batteries UK. 3 V; 14.5 by 25 mm; the half-AA (read 17 October 2026)

Data on this sheet last changed 17 October 2026.