Talk:Celsius

Spelling: Celsius vs Celcius
Can someone explain the origin of the alternate spelling?

I note that the Oxford English dictionary now uses "Celsius", as do Americans and the man's name is "Celsius."

However, it was always "Celcius" when I was at school and University. I've checked with others and they recall being taught the alternate spelling. Perhaps "Celcius" is a better phonetic spelling for an english speaker?


 * Intriguing; never ran across that mistake(?) before myself. There are a lot of hits when you Google on it, too.  Nothing in the Britannica or my other reference works.  Must be another case of bloody American spelling.   :-)


 * Urhixidur 13:57, 2004 Nov 18 (UTC)


 * Enough of the gratuitous America-bashing. Back to your Google

celcius site:.uk       13,800 hits celcius site:.au        7,450 hits
 * Gene Nygaard 05:51, 16 Feb 2005 (UTC)


 * There are some authors of books for schools and universities writing "Celcius", but I have found that my chemistry book for the university uses "Celsius". I think the last is the best way because of two reasons. First, it is fit with the English spelling. Then, it comes from the exact name of the Swedish scientist. Yves Revi 21:31, 27 October 2006 (UTC)


 * I think I've seen both too. However I think you've overlooked one obvious, important reason to prefer "Celsius", namely that it is the standard endorsed by the BIPM:  see  or  ( Incidentally, the latter clearly explains why Celsius is capitalised ).
 * — DIV (128.250.204.118 08:40, 1 September 2007 (UTC))

I'm an American and all books I've ever used here spell it as Celsius. Dave


 * Just noting that the OED doesn't record Celcius at all, not even as a variant. Does anyone have a citation for a reference work with the -c- spelling? 88.19.0.37 (talk) 13:22, 9 January 2024 (UTC)

Confusing conversions in infobox
Part of the infobox to the right →

Infobox at the moment confuses two different notions of "1 degree Celsius". a) the point just above freezing temperature of water and b) difference between, say, 29°C and 30°C. I.e. it confuses an absolute point on centigrade scale, and a relative difference between two points. Template:Infobox unit at the moment is more tailored towards conversions of relative quantities. In the infobox, the formulas in the right column are OK. It is the 1 in the left column that is the issue. Maybe it would be better to split it from the infobox, and add conversion formulas in a separate box? Something like:

—⁠andrybak (talk) 14:42, 8 June 2019 (UTC)


 * Looked a bit into Template:Infobox unit, and after a small tweak, I went ahead, and changed infobox, to make it about absolute temperatures only. —⁠andrybak (talk) 14:58, 8 June 2019 (UTC)

"°С" listed at Redirects for discussion
An editor has asked for a discussion to address the redirect °С. Please participate in the redirect discussion if you wish to do so. Pkbwcgs (talk) 10:54, 19 February 2020 (UTC)

History in the top section?
Shouldn't most of the evolution of the definition of celsius be in the history section. People coming to this page expect the lede paragraphs to give an overview of what the thing is, not multiple definitions over several paragraphs which give conflicting descriptions. &mdash;Memotype:: T 00:55, 23 February 2023 (UTC)

Appropriate mention of Kelvin's derivation in opening paragraph
I've made edits with various wordings, three-times reversed, to indicate that Kelvin has a relationship with Celsius; it's not simply another scale. Historically Kelvin is derived from Celsius; in modern times obviously Celsius is defined in terms of Kelvin. I don't agree that the previous wording is entirely adequate.

I think we can put something in the opening para, perhaps "with same size intervals" or perhaps even just "related scale Kelvin".

First below is how it was; 2 and 3 are two of my wordings.


 * 1) Most countries use this scale; the other major scale, Fahrenheit, is still used in the United States, some island territories, and Liberia. The Kelvin scale is of use in the sciences, with 0 K (−273.15 °C) representing absolute zero.
 * 2) ... The Kelvin scale is of use in the sciences, and was originally derived from Celsius, but with 0 K (−273.15 °C) representing absolute zero.
 * 3) ... The Kelvin scale is of use in the sciences, and is based on Celsius but shifted by -273.15 so that 0 K is absolute zero.

My last edit was to add "closely-related" to "[...] one of two temperature scales used in the International System of Units (SI), the other being the closely-related Kelvin scale." This is in my opinion the best compromise between brevity and informative.

What do others think?

88.19.0.37 (talk) 13:12, 9 January 2024 (UTC)


 * I think it's worth mentioning in the lead. Kelvin is already brought up in the first paragraph, so it's a logical place to put this information. Justin Kunimune (talk) 12:30, 10 January 2024 (UTC)
 * At present we mention the Kelvin scale in the first sentence of the lead, describe it in the last sentence of the first paragraph, repeat that description in the second half of the third paragraph with more details, and then focus the fourth paragraph on the Kelvin scale too.
 * The mention at the end of the first paragraph is only forced on us by the preceding description of Fahrenheit as "the other major scale", as that seems contrary to Kelvin's place in science. Let's change
 * to
 * Together with that, we could implement the IP's third, briefest suggestion and change the end of the first sentence from
 * to
 * without further overwhelming the lead of this article, Celsius. NebY (talk) 13:53, 10 January 2024 (UTC)
 * to
 * without further overwhelming the lead of this article, Celsius. NebY (talk) 13:53, 10 January 2024 (UTC)
 * without further overwhelming the lead of this article, Celsius. NebY (talk) 13:53, 10 January 2024 (UTC)
 * without further overwhelming the lead of this article, Celsius. NebY (talk) 13:53, 10 January 2024 (UTC)