Index / Method

How this site decides

Every number that comes from the manufacturer is reproduced without change. Everything else is arithmetic on those numbers, and this page says exactly what arithmetic.

Fit

Two cells are a drop-in when every cross-section matches within 0.3 mm. That tolerance is the order of a contact spring's travel, not a round number chosen for looks. Outside it the answer is not no: it is shorter, taller, wider or narrower, because those are different problems. A shorter cell enters and may not reach the contact; a taller one will not let the cover close.

Voltage

Classes are set by consequence, and the quantity they are set on is the gap between two nominal voltages taken against the higher of the two. A pair of cells therefore gets one class, whichever of the two pages you meet it on. 2.0% of that gap or less is the same working voltage. Up to 6.0% is close enough that most circuits will not notice but a calibrated instrument might. Up to 20.0% will run and will read off — this is where mercury cells at 1.4 V and alkaline at 1.5 V sit, and why a light meter built for one misreads on the other. Beyond that is a different class. The percentage printed beside a cell is counted from the cell whose page you are reading, so that last boundary falls at 20.0% below it and 25.0% above it: one gap, divided once by the larger nominal and once by the smaller.

Energy

Stored energy is capacity times nominal voltage, in milliwatt-hours, because capacity alone is not comparable across chemistries: 150 mAh at 3 V is twice the energy of 150 mAh at 1.5 V. Density divides that by the published volume. Cells with identical stored energy share a rank rather than being ordered arbitrarily.

The words this site uses

None of these are industry jargon we inherited; they are names we had to pick, so here is what each one means.

Envelope, or shell

The outside size of the cell: a diameter and a height for a coin, three measurements for a box. It is what decides whether the cell goes into the compartment at all.

Drop-in

Every measurement matches within 0.3 mm. It will go in and sit where the old one sat. It says nothing about voltage.

Sits lower

Same diameter, less tall. It will enter, and the contact may not reach it. A spring usually takes it up; a flat tab does not.

Too tall

Same diameter, taller. It goes in and the cover will not close over it.

Reads off

The voltage is far enough from the original that an instrument calibrated for the old cell will show a wrong number. The device still runs. This is the failure people miss.

Not listed

Energizer no longer sells a part under this designation. Other manufacturers may still make the cell.

What the letters in a designation mean

An IEC designation is not a serial number; it is a description. The first letter is the chemistry: L alkaline, S silver oxide, P zinc air, C and B lithium, M mercuric oxide, H nickel-metal hydride, and a bare R carbon zinc. An R after that letter means the cell is round. A W at the end means it meets the IEC watch standard. That is why LR44 and SR44 are the same size and different insides, and why a code beginning with M belongs to a chemistry that is banned from consumer sale in the United States and the European Union.

The designation as a second source

A four-figure IEC code encodes the size: CR2032 means 20 mm across and 3.2 mm tall. Where such a code exists we check it against the published dimensions, which is the only independent check available on a single-source figure. The standard writes whole millimeters, so a cell measuring 12.5 mm is coded 12 — that is rounding, not disagreement, and the pages say which one they are looking at.

Which cells get a page

Not all of them. A designation earns a page when at least 3 of those computed values exist for it and when its text differs materially from every page already published. 215 designations are in the data and 145 have a page. Every one of the rest is in the code index, and those whose envelope carries 3 designations or more are on its shell page as well.

Source: Energizer technical data, retrieved 1 September 2026. Retrieved once and pinned: the site is rebuilt deliberately, not on a schedule, so a page never changes under a reader without the date changing with it.

Trade markings, house codes and what they stand for

Many of the codes stamped on a cheap cell are not designations at all, and 53 of them are resolved to a designation in the table below. An AG number is an importers' convention: no standards body assigns it, no manufacturer is bound by it, and the same AG number has meant slightly different cells at different times. A house code — V13GA, 76A, RW82, KA76 — is a retailer's or a brand's part number for a cell somebody else makes. A ZA number is hearing-aid packaging, colour-coded on the tab.

1 of them — A76 — appears under Also stamped on a cell page all the same, because the maker’s own record carries it as a part number. The rest are not there, because that heading claims the string is physically on the cell under the manufacturer's own record. These are carried separately, resolved to the designation they stand for, and only where that designation exists in this data. Where it does not, nothing is printed: inventing the other half of the pair would look exactly like knowledge.

A trailing W or SW is different again: it is part of the standard and means the cell meets the IEC watch specification, so SR626SW and SR626 are the same envelope with the suffix describing drain rather than size. The search box strips it before looking.

Sources, numbered

Every figure reproduced on this site comes from one of 2 places, and every cell page names the exact records behind it with a link to the sheet. Across the snapshot that is 419 catalog records and 407 technical data sheets.

1. [1] Energizer product data index, data.energizer.com/ — the catalog listing itself: designation, ANSI/NEDA number, chemistry, dimensions, nominal voltage, weight, region and status. Retrieved 1 September 2026.
2. [2] Energizer technical data sheets, data.energizer.com/pdfs/ — one PDF per product, giving capacity and the cutoff voltage it was counted to, volume, impedance, operating temperature range and classification. Each cell page links the sheets it used by filename.
3. [3] IEC 60086, the international standard for primary battery designations, is the authority for the letters and the four-figure size codes described above. It is not reproduced here; it is a paid standard, and this site uses only its publicly documented naming rules.
4. [4] Reese’s Law, United States, 2022 — the federal requirement for child-resistant packaging and warning labels on button and coin cells, cited on the coin-cell pages as the reason those packs are hard to open.

Everything else on the site is arithmetic on the figures in [1] and [2], and every table marks the rows that are ours. The build opens 1 data file, assembled from those 2 and pinned; [3] and [4] are cited for a naming rule and a law, and nothing the site computes comes from either. Where a page would need a figure that is in neither, it says so instead of guessing.

Known limitations

One manufacturer. The domain says cross-reference and this snapshot is one catalog. That is the biggest limitation on the site and it shapes every sentence: a designation missing here is missing from Energizer's catalog, not from the world, and no page claims otherwise. Brand-to-brand columns — the Duracell, Maxell, Renata and Varta equivalents people also want — would need further published catalogs, and until those are read and checked the site does not pretend to them.

Published figures, not measured ones. Nothing here has been on a caliper or a load bank. Where the maker rounds, the site carries the rounding and says so; where the maker publishes nothing, the field is blank rather than estimated, and every cell page lists which of its fields are blank and what that costs the answer.

Fit is geometry only. A drop-in verdict means the outside dimensions agree within 0.3 mm. It cannot see a contact spring's reach, a retaining clip, a polarity difference in a holder, or a compartment that vents. A cell that fits is not thereby a safe substitute.

Rechargeables are compared but never recommended. They appear in tables because they share envelopes, always with their nominal voltage and never as a drop-in for a primary cell.

Update frequency. The snapshot is taken deliberately, not on a schedule, and the date it carries is the date of the data. A rebuild that changes nothing changes no page. When the catalog is read again the previous snapshot stays available as a dated CSV, so the difference between two dates is itself checkable.