Index / Battery sizes and types

Find a cell — type the code stamped on it, or its size in millimeters

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Battery sizes and types

The name on the packet is a shape, not a specification. Each of these sizes is made in more than one chemistry, and more than one of them is made in more than one voltage, so the types of batteries sold under one size name are not the same cell.

Fit answers whether it enters the compartment. Voltage answers whether the circuit will notice. A cell that fits is not always a safe substitute.

What the table shows when you read down it

Across the 10 sizes here the data holds 56 designations, and 33 of them are no longer listed by the maker — 58.9 of the whole. That share is the reason this site exists: the code stamped on a cell in a drawer is more likely to be a name the catalog has dropped than a name it still sells.

AA spans the most chemistries: 5 kinds different kinds share that one name, which means a compartment marked with it will physically close on cells that behave differently in the circuit.

Lantern holds the widest voltage spread of any size here, 10.5 V between its lowest and its highest. Nothing about the holder warns which one the device was designed around, and no figure on this site can tell you what the device does with the difference — only what the difference is.

Lantern is the least consistent in length: 30 mm between the shortest and the longest designation carrying that name. The tolerance this site treats as a drop-in is 0.3 mm, the order of the spring travel in a contact, so the ends of that range are not the same part.

Every figure above is computed from the snapshot named at the foot of this page, not copied from a table anywhere. Where the maker publishes nothing for a designation, it is counted in the totals and left out of the averages rather than filled in with a guess.

Every size in one line

The table above answers one row at a time. The question people actually arrive with is comparative — whether the name on their cell covers one voltage or a range, and how wide the range is. Here is each size as a single line, with the figures that decide a substitution rather than the figures that describe a catalog.

size

A range in that list is a warning, not a detail. Where a name covers more than one voltage, the holder closes on all of them and nothing in the device says which it expects; where it covers more than one height, the taller one may hold the lid open. Both are answered on the page for that

AA — 11 designations, 5 still listed, 1.2–1.5 V, 47.6 to 50.5 mm tall.

AAA — 6 designations, 4 still listed, 1.2–1.5 V, 42.8 to 44.5 mm tall.

AAAA — 3 designations, 1 still listed, 1.5 V, 39.8 to 42.5 mm tall.

C — 7 designations, 3 still listed, 1.2–1.5 V, 46.7 to 50 mm tall.

D — 8 designations, 3 still listed, 1.2–1.5 V, 57 to 61.5 mm tall.

N — 3 designations, 1 still listed, 1.5 V, 27.9 to 30.2 mm tall.

9V — 5 designations, 4 still listed, 7.2–9 V, 44.5 to 49 mm tall.

J — 2 designations, 0 still listed, 6 V, 48.5 mm tall.

F — 2 designations, 0 still listed, 1.5 V, 87.8 mm tall.

Lantern — 9 designations, 2 still listed, 1.5–12 V, 97 to 127 mm tall.

, cell by cell, with the drawing at real scale.

Why this list is shorter than the data

The snapshot holds 16 sizes in all; 10 of them are shown above. A size earns a page here when at least 2 designations share it, because below that there is nothing to compare: a page that lists one cell and calls it a group answers a question nobody asked. The 6 sizes left out are not missing from the site — every designation in them has its own page or its own row in the code index, which carries all of them with no threshold at all.

The threshold is a property of this list, not of the world. A cell whose envelope is shared by nobody else is still a real cell, and the fact that nothing else is made in its shape is itself the answer to a substitution question: there is no drop-in, and the search box will say so by size.

Why one cell answers to several names

The 56 designations in this table carry 225 names between them, because a battery is named by separate systems that were never meant to agree, and then by whoever sells it. The IEC designation is the one that carries information: the first letter is the chemistry and the digits are the size, so BR1225 says lithium, 12.5 mm across and 2.5 mm tall. This site decodes that and checks it against the published measurement, which is the only independent check available when the data comes from a single maker.

The ANSI/NEDA number carries no geometry at all; it is a catalog entry. The name on the packet — the one in the left column of the table above — is a shape people recognize and is not a specification: it says nothing about voltage or chemistry, which is why every size in this table is made in more than one of both. And the part number the maker prints belongs to that maker's line rather than to the cell.

In this table 32 of the 56 designations carry more than one name, and the busiest of them answers to 19 names. That is why the search box takes any of them and why a code that finds nothing is worth measuring instead of retyping: the name you are holding may belong to a system this catalog does not use, while the cell itself is here under another.

Those names appear on real packaging, often on the same box, and none of them is wrong. The search box on this site accepts any of them, because the person holding the cell did not choose which system stamped it. Where a name belongs to a company whose catalog is not the source of this data, it is listed as a name and not as a designation: the cross-reference answers what fits, and equivalence of brand is a claim this site does not have the records to make.

Where these numbers come from

Dimensions, voltages, chemistries and capacities are published by the manufacturer and reproduced without change. Everything else on the page is ours, computed from those figures: whether one cell fits where another sat, how far apart their voltages are, stored energy and energy per cubic centimeter, the rank within a shell, and the check of the designation against the measured size.

Fit is decided within 0.3 mm on every axis, which is the order of a contact spring's travel. Voltage classes are decided by consequence, not by roundness, and they are decided on the gap between two nominal voltages taken against the higher of the two: 2.0% or less of it is the same working voltage, 6.0% starts to matter to a calibrated instrument, and past 20.0% it is a different class altogether. Measuring the gap against the higher figure is what makes the verdict the same from either cell’s page, while the printed percentage stays counted from the cell you are reading about. Cells with identical stored energy share a rank instead of being ordered arbitrarily.

Ranking uses capacity times nominal voltage, because capacity alone is not comparable across chemistries: 150 mAh at 3 V is twice the energy of 150 mAh at 1.5 V. Neighbors are chosen by measurement and never alphabetically, because two cells filed next to each other by name usually have nothing in common. A blank in any table means the maker publishes no figure, which is not the same as zero.

Source: Energizer technical data, retrieved 1 September 2026.

Before you swap anything

Everything here is computed from published dimensions and nominal voltages. That answers whether a cell enters the compartment and whether the voltage matches on paper. It does not answer what your device does with the difference, and it cannot: a cell that fits can still be the wrong cell.

One more limit, and it is the biggest. This site reads a single manufacturer’s catalog. When a page says a designation is not listed, that means Energizer no longer offers a part under it — not that nobody makes the cell. Other makers may still sell it, and for common sizes they usually do.

A voltage difference is one relation between two cells, and this page prints it from the cell it is about — in every table on the page, including the one listing cells no longer made. A figure always belongs to the cell whose voltage is printed beside it: a cell that runs lower than this one carries a minus here, one that runs higher carries a plus, and two cells at the same nominal voltage carry zero. Meet the same pair on the other cell’s page and the sign is the other one, with the figure taken against that cell instead of this one; where the two run at the same voltage, both pages print zero. The class beside the figure is not read off that figure directly. It is decided on the gap itself, taken against the higher of the two nominal voltages, so one pair of cells gets one class whichever page you meet it on: counted from this side the boundary of the class that still runs falls at 20.0% below and 25.0% above, which is the same gap divided once by the larger nominal and once by the smaller. What genuinely differs between the two directions is the consequence, and the words carry it: a cell that runs low makes a calibrated instrument read below true, and a cell that runs high makes it read above.

3 things this site cannot see. Whether the contacts reach a shorter cell. Whether the device was calibrated for a chemistry that holds its voltage flat, which silver oxide does and alkaline does not. Whether the equipment tolerates the higher current a different chemistry can deliver. Rechargeable cells are never a drop-in for primary cells regardless of size.