When I needed one, I couldn’t find an ip complement/consolidate calculator on the internet (or maybe I didnt search hard enough), so I created on for myself.

To me it seems to be working correctly, however I would appreciate any test or comment from your side. It is reachable here: https://ipcalc.gergovadasz.hu/

It is running on a small server, so the consolidate calculate will take some time if you try with thousands of IPs, but it should work correctly, hopefully.

Any comment, feedback is appreciated.