How calculate TextSize, to adjust it's height correctly?

Hello guys. I’m trying to calculate text size, so it will have certain height. BUT IDK which formula I need use, because sometimes text size got actually increased, and sometimes not:
Some textSizes skipped, because they just don’t affect real text size at all.

You may utilize TextService’s GetTextSize for this. Judging by your photo, use the Y value of the returned Vector2 value:

local TextService = game:GetService("TextService")

print(TextService:GetTextSize("Hello world!", 16, Enum.Font.RobotoCondensed,, 100)).Y)

It looks like TextHeight = TextSize/2

It might just be TextHeight = TextSize