I have no idea why this hasn't been invented yet...

[CurlewKate]

Some way of simply testing a chilli to see how hot it is. Like litmus paper? It must be possible.

Dab it on your tongue

That's what your taste buds are for

I know- that's what I do. But some people are scared to do that-(looking at you, dd!)-and there must be a technological solution!

It’s not cheap though https://www.zimmerpeacocktech.com/2017/08/26/chillipot-chilli-hotness-sensor/

I just get my husband to test for me

There's the scoville scale. If you know what type of chilli it is, you can google to see where it fits in.

Eg jalapenos are 'mild hot'
scotch bonnets are 'spicy hot' and
nagas are 'fiery hot'

https://scovillescale.org/chili-pepper-scoville-scale/