Not sure if i understand. I think your asking how to find the exact IV's not just the IV tier. You can use this site or one of the many APP's. I like PoGo Master because its fast and easy yo use on my phone.
https://pokemongo.gamepress.gg/pokemongo-iv-calculator
https://play.google.com/store/apps/details?id=com.fancydevs.pokegomaster&hl=en
