How do I read 100°C in Japanese?

Question

In English, I just read it "one hundred degrees Celsius".
In Japanese, I don't know how to read it.

Answer 1

It is in a slightly different order in Japanese.

First comes Celsius, then the amount, and degrees at the end.

This would be one hundred degrees Celsius written out:

摂氏{せっし}100度{ど}

Fahrenheit for example would be similar

華氏{かし}100度{ど}

Most of the time saying Celsius is redundant though. If someone asks you what is the temperature, you can just say 26 degrees.

気温{きおん}は何度{なんど}？

今{いま}、26度{ど}。

Answer 2

The reading depends on the situation. In a scientific or technical environment Chris's answer is 100% correct.

However, in conversational non-technical situations it is read differently.

When speaking with someone you can say

[度シー]{どしー}

for Celsius. However, in Japan the standard for expressing temperature is metric, so there is no need to clarify that you are using the metric system. Saying the number and [度]{ど} will suffice.

This can be proven a number of different ways.

First, if you have a Japanese IME on your computer or device and you understand how to convert characters you can simply type in どしー into your device and press the conversion button. You'll see that the IME will bring up ℃ as a conversion option (depending on the IME in use).

If you would like to refer to Fahrenheit in a conversational or casual situation you can say

[度エフ]{どえふ}

Here is a link to a question on Yahoo Japan's Knowledege Bag where a Japanese person is asking how to read ℃ and °F. The quote on reading Celsius and Fahrenheit is listed and very roughly translated below.

[当然]{とうぜん}、[℃]{せっしど}も「[度]{ど}シー」というのと[同様]{どうよう}[°F]{かしど}も「[度]{ど}エフ」と[読]{よ}めば、[紛]{まぎ}らわしくありません
Just as Celsius can be read as degrees C, reading Fahrenheit as degrees F will naturally reduce ambiguity [between the two temperature systems].

On a side note, typing どえふ into your IME and converting it does not yield the same result. From what I have seen, it doesn't look like °F has a unicode or UTF-8 character. It is for this reason that if you highlight °F with your mouse you will highlight two characters, but if you highlight ℃ with your mouse you will only see one character highlighted.

Answer 3

We say usually only 度 like 100度 because only Celsius is commonly used in Japan, so we don't need to say 摂氏.