Is Codex Free? GPT-6 Sol, ChatGPT Work, CLI, Credits, and API

How far the Free plan goes

Free gets Codex in one place, the desktop app, on one model, GPT-6 Luna. "Subject to rollout" means Luna in Codex may not have reached every Free account yet.

OpenAI's published message estimates cover Plus and Standard Business, and we found no figure for Free or Go. Plus is sold with "expanded Codex usage", and on Plus OpenAI estimates 350 to 3,000 local Luna messages per five hours, so expect less than that on Free. Because Codex and ChatGPT Work share one allowance, heavy Work use on Free also shortens your Codex time.

When Free runs out, there is no credit top-up: OpenAI sells extra credits to Plus and Pro users and to Business, Edu and Enterprise workspaces on flexible pricing. You can wait for the limit to reset, or keep working locally by signing Codex in with an API key, which bills every token.

The first paid step depends on where you want to code

The second column decides it. If the desktop app is enough, Free or Go covers you; the terminal or an IDE costs either $20 a month or per-token billing.

For light terminal use, an API key on GPT-6 Luna can cost less than Plus; Codex CLI cost prices an illustrative task on each model. For Codex, Go is worth $8 only if the desktop app is enough; ChatGPT Go vs Plus covers what else it adds.

Code you do not own: training defaults differ by plan

OpenAI lists no training on your data by default only for Business, Enterprise and API-key use. Go, Plus and Pro use your content for training unless you opt out, and OpenAI's plan comparison does not state Free's default. If the repository belongs to an employer or a client, check those settings before pointing a personal Free account at it, or use an API key or a Business workspace. Business starts at two users, at $25 per user billed monthly.

For how credits and API billing stay apart once you pay, see Codex credits vs API billing.