[j1elo]

Funnily enough, the scale on the linked page doesn't allow me to set -40°. It jumps between -39.9 and -40.1

So seems like -40.0 is really where the singularity lies.

Either that, or a simple rounding issue. I choose to believe it's the former.

[perilunar]

Not a rounding error in this case, but more to do with the precision of your input device and your screen size. The input angle and the converted temperatures are rounded to the nearest 0.1 degrees, but it is possible to hit 40.0° (I should probably add an option to round to whole degrees.)

If you really want to hit an exact number, you can add a query string to the URL.

https://degreeswhat.com/?-40

[joshspankit]

If you’re using a touch display, it’s easier to land on specific numbers by moving your finger away from the centre. The further your finger, the finer the adjustment.

[imglorp]

Remember that time when it was a rounding error?

https://www.theverge.com/tldr/2021/7/13/22575368/apple-ios-1...