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

The Celsius and Fahrenheit scales meet at exactly minus 40 degrees. The figure is taken from NIST, 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 science fact?

Yes. It sits on the Science 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

Minus forty is the same in both scales

The Celsius and Fahrenheit scales meet at exactly minus 40 degrees The two scales start at different zero points and use different step sizes, so their readings cross at one temperature. That point is minus 40, where minus 40 degrees Celsius and minus 40 degrees Fahrenheit describe the same air. Convert in either direction and the two numbers come back identical. It sits in Mondo's science collection, one of 200 facts that each trace back to the reference below.

Where this comes from

NIST

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: measurement, temperature, units

Minus forty is the same in both scales: the short answers

Where does this come from, and can I check it?: The Celsius and Fahrenheit scales meet at exactly minus 40 degrees. The figure is taken from NIST, 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 science fact?: Yes. It sits on the Science 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.