Font size in Nextion and Illustrator

I’m making a layout of my design for Nextion in Adobe Illustrator. And I noticed that the physical font size in Illustrator is larger than in Nextion for the same pixel sizes.
Is this normal or am I doing something wrong or something?
Thank you.

Hi and welcome @DrEmmettBrown!

I think I got an explanation, though I haven‘t verified it. Illustrator gives you the ‘perceived’ height of the letters, f.ex. the height of letters like A, B, f. However, there are letters that exceed the upper/lower height of this ‘average’ sizes letters, most notably letters like p, q, y. They don‘t look taller though because they‘re basically just shifted.
However, what matters for Nextion and their users, is how high does the textbox need to be such that all letters fit in there. This is effectively a ‘peak to peak’ measurement. The box needs to be tall enough to get both the lowest end of a p in there as well as the highest end of an L. And that‘s how Nextion defines font size.

Unfortunately there‘s no general way of convert between both because the proportions vary from font to font. However, I‘d bet that the ratio between both values is constant across all sizes for a given font. So you measure it once and then adjust all font sizes in illustrator by that factor.

Kind regards,