The AI Models Index tracks premium model releases from 15 labs since 2023, with...

https://lanesniceblog.scriblorax.com/posts/why-does-gpt-5.2-cost-more-than-gpt-5.1

The AI Models Index tracks premium model releases from 15 labs since 2023, with verified dates and blind-vote checks for accuracy. Updated every two weeks, it reveals a 56% improvement rate in model quality