I use Pro in a browser to massively improve my productivity. I’m not using an API-based CLI or IDE integration although I understand there are many advantages to doing so.

I continue to see people posting about “Codex.” AFAIK, no such thing exists anymore.

I’m confused about people mean when they use the word “Codex.” I asked ChatGPT Pro in my browser what it means these days and it said this:

“It refers to the old OpenAI Codex model family (code-davinci-002, code-cushman-001) that powered GitHub Copilot and early “Codex” web playgrounds. Those endpoints were shut down in March 2023. At that time: • “Web version” meant the Codex web playground on platform.openai.com. • “CLI version” meant using the OpenAI API directly from a command-line script.

They were the same model, only the rate-limits differed (the web UI had higher soft limits).

Today there is no separate Codex product. GPT-4-class models (4o, 4-turbo, 5) contain all the code training Codex had and more.”

And earlier in the chat, it said all this:

“Codex is no longer a selectable model. OpenAI integrated code-focused capabilities into GPT-4 and GPT-5, so there is no separate “Codex” button in the current ChatGPT iOS app—even on Pro accounts.

If you need code-generation or code-completion features, just stay on GPT-4 or GPT-5 (Auto, Instant, or Thinking). Those already include everything Codex provided.”

And this:

“The Codex models are retired. API calls to code-davinci or code-cushman endpoints now fail or are routed to GPT-4-turbo equivalents. Current code-capable options are GPT-4-turbo or GPT-4o (and GPT-5 when available). These have the Codex training baked in and outperform the old Codex on code generation, reasoning, and review.

So using “Codex via the API” will not give better results. Use the latest GPT-4 or GPT-5 API models instead.”

So, what’s is the “Codex” posters continue to refer to? Are they simply misinformed?