Where does this come from, and can I check it?

The four digits give diameter in millimetres and thickness in tenths. The figure is taken from International Electrotechnical Commission, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a everyday life fact?

Yes. It sits on the Everyday Life shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

What else can I read about it?

The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

CR2032 coin cell codes hide diameter and thickness

The four digits give diameter in millimetres and thickness in tenths In the code CR2032, C means a lithium manganese dioxide chemistry, R means round, and the digits give a 20 millimetre diameter and 3.2 millimetre thickness. The convention lets a replacement be matched without a ruler, though suffix letters also encode contact and discharge details. Button cells power watches, key fobs and kitchen scales. It sits in Mondo's everyday life collection, one of 200 facts that each trace back to the reference below.

Where this comes from

International Electrotechnical Commission

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: batteries, electronics, naming

CR2032 coin cell codes hide diameter and thickness: the short answers

Where does this come from, and can I check it?: The four digits give diameter in millimetres and thickness in tenths. The figure is taken from International Electrotechnical Commission, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a everyday life fact?: Yes. It sits on the Everyday Life shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.