# API keys Create, protect, and replace the key used to authenticate requests. ## Create a key Sign in and open [Account → API keys](https://deepseeksub.com/account/keys). Choose a name, billing mode (Auto, Plan only or API credit only), and expiry (30, 90 or 365 days). Copy the key immediately; the complete value is shown only once. Up to 20 active keys are allowed per account. Keys access `deepseek-flash` and require an active plan or API credit. ## Store it securely Treat the key like a password. Use an environment variable or a secret manager. Do not place it in source code, share it in screenshots, or commit it to a public repository. On macOS or Linux, set a key in the current terminal session: ```sh export CODING_PLAN_API_KEY="your-api-key" ``` On Windows PowerShell: ```powershell $env:CODING_PLAN_API_KEY = "your-api-key" ``` These commands affect the current terminal session; opening a new terminal requires setting the variable again. ## Replace an exposed key If a key has been exposed, revoke it in Account → API keys in your signed-in account. Create a replacement and update each application that uses the old key. Never post the key when asking for help. ## Troubleshooting A 401 response usually means the key is missing, invalid, or revoked. Check that the correct key is being sent to the intended service endpoint. A key from the official DeepSeek platform and a key from this independent service may not be interchangeable. --- HTML source: [API keys — DeepSeek Subscription Tutorials](https://deepseeksub.com/docs/api-keys/)