ANTHROPIC_API_KEY

Updated October 13, 2026 by Alex Sorokoletov

ANTHROPIC_API_KEY is a Claude Code environment variable: Primary API key for Claude API. Its release history is not tracked here. It is listed in the official reference.

Status	Present in v2.1.294
Category	Authentication
Official docs	Listed

How to set it

For one session, export it in the shell that starts Claude Code:

export ANTHROPIC_API_KEY=<value>
claude

To apply it to every session, add it to the env object of a settings file:

// ~/.claude/settings.json
{
  "env": {
    "ANTHROPIC_API_KEY": "<value>"
  }
}

Release notes that mention it

Related variables

CLAUDE_CODE_API_KEY_FILE_DESCRIPTOR: File descriptor to read API key from.
CLAUDE_CODE_API_KEY_HELPER_TTL_MS: Cache TTL for API key helper.
ANTHROPIC_AUTH_TOKEN: Alternative bearer token; takes priority over API key.
CLAUDE_CODE_CLIENT_KEY: Path to client private key.
CLAUDE_CODE_CLIENT_KEY_PASSPHRASE: Passphrase for encrypted client key.
CLAUDE_LOCAL_OAUTH_API_BASE: Overrides the base URL for local OAuth API operations.
CLAUDE_CODE_ARTIFACTS_API_TOKEN
CLAUDE_CODE_MEMORY_API_TOKEN

Frequently asked questions

What does ANTHROPIC_API_KEY do?

Primary API key for Claude API

Which Claude Code version has ANTHROPIC_API_KEY?

Its release history is not tracked here.

How do I set ANTHROPIC_API_KEY?

Export it before starting Claude Code (export ANTHROPIC_API_KEY=value), or add it to the "env" object in ~/.claude/settings.json to apply it to every session.

All variables, searchable: Claude Code environment variables.