AIBU to not understand levi jeans sizing?

[Newernewist]

Just that.
Im looking at Levi jeans on their website
The sizing is v strange.
Ive seen a pair of shorts for me, uk size 12, nearly 14 (lockdown) so i I think a 31w.
But then there are some shorts in size 12A.
Is there a link to a size calculator or guide for Levi Jeans somewhere?

My daughter is in age 12 clothes so if the 12A is a child size that's brilliant

Buggered if I understand it either. Pre lockdown I went into Next to buy jeans and I couldn't fathom it at all. They were all skinny, stovepipe, bootleg etc when what I needed was 'huge arse'. I just gave up.

There is a size guide here: www.levi.com/GB/en_GB/cms/sizeguide

You need to dig out a tape measure and measure your waist and inseam. Jean size 31 equates to a 32.75 inch waist. Size 12A is a child's size for 12-year-olds.