> ## Documentation Index
> Fetch the complete documentation index at: https://docs.parzo.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Authentication

> How to authenticate with the Parzo API.

## API Keys

All requests require an API key passed in the `X-API-Key` header.

```bash theme={null}
curl https://api.parzo.dev/v1/extract/invoice \
  -H "X-API-Key: inv_your_key_here"
```

## Getting your API key

<Steps>
  <Step title="Sign up">
    Create a free account at [parzo.dev](https://parzo.dev). No credit card required.
  </Step>

  <Step title="Go to API Keys">
    In your dashboard, navigate to **API Keys**.
  </Step>

  <Step title="Create a key">
    Click **Create Key**, give it a name (e.g. `Production`), and copy it immediately — it's shown only once.
  </Step>
</Steps>

## Key format

All Parzo API keys start with `inv_` followed by 32 random characters.
inv\_A3kB9mXp2rQwF7cL1xNvJ6dS4hT8uE0y

## Best practices

<Warning>
  Never expose your API key in client-side code, public repositories, or logs.
</Warning>

Always store your key as an environment variable:

```bash theme={null}
# .env
PARZO_API_KEY=inv_your_key_here
```

```python Python theme={null}
import os
api_key = os.environ["PARZO_API_KEY"]
```

```javascript Node.js theme={null}
const apiKey = process.env.PARZO_API_KEY;
```

## Multiple keys

You can create multiple keys — for example one for production and one for staging. Each key:

* Tracks its own usage independently
* Can be revoked without affecting other keys
* Has the same quota as your plan

## Revoking a key

Go to **Dashboard → API Keys**, click the three dots next to the key, and select **Deactivate**. The key stops working immediately.