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

# Introduction

> Fundamental concepts of Tally's API.

## Base URL

The Tally API follows REST principles and is accessible only via HTTPS. For security reasons, unencrypted HTTP requests are not allowed. The Base URL for all API endpoints is:

```bash Terminal theme={null}
https://api.tally.so
```

## Authentication

Authentication to the Tally API requires an Authorization header with a Bearer token. Include the Authorization header in your requests as shown below:

```bash Terminal theme={null}
Authorization: Bearer <token>
```

Learn more about [how to get your API key](/api-reference/api-keys).

## Response codes

The API returns standard HTTP response codes to indicate the success or failure of an API request. Here are a few examples:

| Code  | Description                                                             |
| ----- | ----------------------------------------------------------------------- |
| `200` | Success - The request completed successfully                            |
| `400` | Bad Request - The request was malformed or contained invalid parameters |
| `401` | Unauthorized - Authentication credentials are missing or invalid        |
| `403` | Forbidden - You don't have permission to access this resource           |
| `404` | Not Found - The requested resource doesn't exist                        |
| `429` | Rate Limited - You've exceeded the allowed number of requests           |
| `500` | Server Error - Something went wrong on our end                          |

## Rate Limits

To ensure fair usage and maintain service quality, the Tally API limits requests to 100 per minute.

<Tip>
  <b>Avoid rate limits with webhooks!</b> Instead of polling for new form submissions, use
  [webhooks](https://tally.so/help/webhooks) to receive data instantly when forms are submitted.
  This is more efficient and won't count against your rate limit.
</Tip>