open weightsA model whose trained parameters are published for anyone to download and run — unlike API-only models you can access but never possess.Full definition → models lag closed frontier models by about four months on Epoch's aggregate index. That gap helps you decide when self-hosted or open models are a viable substitute for closed APIs.
Terms in this piece · Glossary
open weights — A model whose trained parameters are published for anyone to download and run — unlike API-only models you can access but never possess.
