auth.md Codex Docs, 2026-05-14 21:00 UTC → 2026-05-18 22:01 UTC

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21When you sign in with ChatGPT from the Codex app, CLI, or IDE Extension, Codex opens a browser window for you to complete the login flow. After you sign in, the browser returns an access token to the CLI or IDE extension.21When you sign in with ChatGPT from the Codex app, CLI, or IDE Extension, Codex opens a browser window for you to complete the login flow. After you sign in, the browser returns an access token to the CLI or IDE extension.

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23If your environment already provides a ChatGPT access token, the CLI can read

24it from stdin:

25 

26```shell

27printenv CODEX_ACCESS_TOKEN | codex login --with-access-token

28```

29 

23### Sign in with an API key30### Sign in with an API key

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25You can also sign in to the Codex app, CLI, or IDE Extension with an API key. Get your API key from the [OpenAI dashboard](https://platform.openai.com/api-keys).32You can also sign in to the Codex app, CLI, or IDE Extension with an API key. Get your API key from the [OpenAI dashboard](https://platform.openai.com/api-keys).

116If your network uses a corporate TLS proxy or private root CA, set123If your network uses a corporate TLS proxy or private root CA, set

117`CODEX_CA_CERTIFICATE` to a PEM bundle before logging in. When124`CODEX_CA_CERTIFICATE` to a PEM bundle before logging in. When

118`CODEX_CA_CERTIFICATE` is unset, Codex falls back to `SSL_CERT_FILE`. The same125`CODEX_CA_CERTIFICATE` is unset, Codex falls back to `SSL_CERT_FILE`. The same

119custom CA settings apply to login, normal HTTPS requests, and secure websocket126custom CA settings apply to login, normal HTTPS requests, and secure WebSocket

120connections.127connections.

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122```shell129```shell