> **For coding agents and LLMs:** This is one Social Fetch marketing page (markdown export). For API orientation start with [`/llms.txt`](https://www.socialfetch.dev/llms.txt); for auth and crawl rules use [`/agents.txt`](https://www.socialfetch.dev/agents.txt); for every operation use [`/llms-endpoints.txt`](https://www.socialfetch.dev/llms-endpoints.txt).

## This page

- **On-site (HTML):** <https://www.socialfetch.dev/platforms/mastodon/servers-host-peers>
- **Markdown (.mdx) URL:** <https://www.socialfetch.dev/platforms/mastodon/servers-host-peers.mdx>

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# Mastodon Peers API

Every domain a server has seen, filtered by text and sliced into pages, up to 1000 per request.

`GET /v1/mastodon/servers/mastodon.social/peers` returns `data.peers`, the domains the server has federated with, along with `data.totalPeers` for the whole list or the filtered count, `data.query` and `data.page`. `q` filters to domains containing the text, case-insensitively. The list includes dead domains and servers running other software, because it records what the server has seen, not what is reachable now.

The full list is one document, so every page fetches it and slices a different part. `limit` accepts 1 to 1000 and defaults to 100. The cursor holds the last domain served as well as the offset, so a peer added or dropped between pages does not make the next page repeat or skip a row when the anchor is still in the list. This is the largest Mastodon route: some lists run to six figures of domains, so use a text filter when you do not need all of them.

## Request

- **Endpoint:** `GET /v1/mastodon/servers/{host}/peers`
- **Credits:** 1 credit
Failed requests are free
- **Input:** by host
- **Full reference:** [docs](https://www.socialfetch.dev/docs/api/v1/mastodon/servers/host/peers/get)
- **Platform page:** [/platforms/mastodon](https://www.socialfetch.dev/platforms/mastodon)

## FAQ

### How large is a peer list?

Large servers can list tens of thousands of domains, and the largest measured list had 125,725. Page size defaults to 100 and can go to 1000, but a full pull still takes many requests.

### How many credits does a page cost?

Pricing is documented on the operation in the API registry (shown on this page). Confirm on every response with meta.creditsCharged: that field is the billing source of truth. Each paginated page is a separate billed request.

### Does the list mean those servers are alive?

No. It records domains the server has seen, including dead domains and servers that run other software. Check a domain with the server route before relying on it.

### How do I filter the list?

Send q with text such as photography. The filter is a case-insensitive substring match on the domain, and totalPeers becomes the matching count.

### Why is the peer list unsupported?

Some operators switch the peer list off. That returns unsupported with an empty list rather than a forbidden or missing host.