1999 ZX2 Rim Size

What size rims are on a 1999 ZX2 Sport? They are the swirl pattern. I thought they were 15 but I measured 16. Maybe I measured from the wrong spot? Does anyone know what they are officially? Any help much appreciated cuz I am looking into swapping them out for some 2003 5 spoke and I was hoping they are the same size.

they're both 15".

"tip" you can always look at the tire first (3 digit) number is width in mm 2nd numer is the height of the sidewall as a percentage of the width and the last number is the size of the rim the tire fits onto