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

# Get Referring Domains

> Get how many distinct domains link to a domain, and the 20 strongest of them with their Site Strength.

`GET https://rankfield.dev/v1/domains/{domain}/referring-domains`

```bash cURL
curl 'https://rankfield.dev/v1/domains/cloro.dev/referring-domains' \
  -H 'Authorization: Bearer YOUR_API_KEY'
```

```python Python
import requests

response = requests.get(
    "https://rankfield.dev/v1/domains/cloro.dev/referring-domains",
    headers={"Authorization": "Bearer YOUR_API_KEY"},
)
print(response.json())
```

```javascript JavaScript
const response = await fetch("https://rankfield.dev/v1/domains/cloro.dev/referring-domains", {
  headers: {
    "Authorization": "Bearer YOUR_API_KEY",
  },
});
console.log(await response.json());
```

```json 200
{
  "domain": "cloro.dev",
  "referringDomains": 68,
  "topReferrers": [
    { "domain": "vercel.app", "siteStrength": 89, "observations": 1 },
    { "domain": "it.com", "siteStrength": 88, "observations": 1 },
    { "domain": "langchain.com", "siteStrength": 75, "observations": 1 },
    { "domain": "artdaily.com", "siteStrength": 70, "observations": 1 }
  ]
}
```

## Parameters

### Headers

| Name | Type | Required | Default | Description |
|---|---|---|---|---|
| `Authorization` | string | Yes | – | `Bearer` followed by your API key. See [Authentication](/docs/get-started/authentication). |

### Path parameters

| Name | Type | Required | Default | Description |
|---|---|---|---|---|
| `domain` | string | Yes | – | The domain, such as `example.com`. Case is ignored, a leading `www.` is removed, and a full URL is read as its host. URL-encode it in the path. |

## Response

| Field | Type | Description |
|---|---|---|
| `domain` | string | The domain as it was looked up. |
| `inGraph` | boolean | Only when the domain isn't in our link graph yet: `false`, with zeros. Absent otherwise. |
| `referringDomains` | integer \| null | How many distinct domains link to it in the graph. `null` when the count is unavailable: keep it as unknown, not zero. |
| `topReferrers` | array | Up to 20 referring domains, strongest first (the example shows 4). |
| `topReferrers[].domain` | string | The linking domain. |
| `topReferrers[].siteStrength` | integer \| null | Its Site Strength, `null` when it has no score. |
| `topReferrers[].observations` | integer | `1` marks one domain-to-domain link in the graph. It is not a count of pages or backlinks. |

To get every referring domain, not only 20, use [List All Referring Domains](/docs/referring-domains/list-referrers).

## Errors

| Status | When |
|---|---|
| 400 | The domain is not a valid domain name, or a parameter is out of range. |
| 401 | No valid API key. |
| 429 | Too many requests at once; wait for `Retry-After`. |
| 502 | The graph lookup behind the API failed. Retry later. |
| 503 | The graph index is unavailable for a moment. Retry after `Retry-After`. |

## Limits

No per-key limits. When the server is busy you get `429` with `Retry-After`.

## MCP

On the [MCP server](/docs/agents/mcp-server), the tool for this is `get_referring_domains`.