One really good site I found for checking ID on butterflies, moths and caterpillars is Butterflies and Moths of North America:
https://www.butterfliesandmoths.org/
If you click on their Image Gallery at the top of the page you'll find a ton of pages with about 48 photos per page. No need to join in order to use their photo database. Once in the gallery you can sort for caterpillar, butterfly or moth as well as Family, Sub-Family etc to zero in somewhat on what you're looking for.