How to post to Mastodon from n8n

Post to Mastodon from n8n, step by step

About ten minutes, on the free plan. On Oct 27, 2026 n8n's list of built-in app nodes went from Matrix and Mattermost straight to Mautic: there is no Mastodon node to configure, which is why the steps start with PostWire.

1. Create a free PostWire account

   Open postwire.io/dashboard.html, type your email and press Create my free account. PostWire emails you a link to confirm the address; connecting accounts and publishing unlock once it is confirmed. No password and no card (free plan: 1 business, 10 posts a month, 5 AI drafts a day (about 20 a month), 2 networks per post, 3 scheduled posts at a time — every network connects free, no card).

2. Create an access token on your Mastodon server

   In Mastodon open Preferences → Development → New application, give it a name, tick write:statuses and write:media, save, and open the application to copy Your access token. It works for your account on that server only, and deleting the application in Mastodon disconnects PostWire.

3. Connect Mastodon

   In the dashboard open Accounts, press Connect on Mastodon and paste your server's address (for example https://mastodon.social, or your own instance) and the access token. The address has to be a public https server.

4. Copy your API key

   In the dashboard, open API & MCP and press Copy key on the API key card. It is sent as Authorization: Bearer pw_live_… (the X-API-Key header also works). Keep it server-side.

5. Install the PostWire node

   In n8n: Settings → Community nodes → Install, enter n8n-nodes-postwire (version 0.4.3 on npm on Oct 27, 2026), then add a PostWire API credential with the key and press Test, which checks the key at once. Where community nodes cannot be installed, the HTTP Request node further down does the same job.

6. Configure Post → Publish

   Networks: Mastodon. Content: Smart Distribute: Write a Native Post per Network, with the Idea from the previous node: the Mastodon draft stays within 500 characters, community-first, no marketing-speak, with 2 to 4 CamelCase hashtags, which screen readers read out word by word. To send your own words, set Content to Same Text on Every Network. Media: URL or Binary File for an image or a video. For a thread, Options → Thread lists the posts after the first, First Comment adds a reply under the last one, and Split Long Text Into a Thread cuts a long text into toots itself.

7. Or one HTTP Request node

   POST to the REST API with header Authorization: Bearer pw_live_…. media takes up to 4 attachments, photos or a video, each with its own alt; per_platform.mastodon.thread takes the posts after the first (up to 9), or true:

   POST https://postwire.io/api/post
   Authorization: Bearer pw_live_…
   Content-Type: application/json
   
   {
     "platforms": ["mastodon"],
     "per_platform": { "mastodon": {
       "text": "Episode 42 is out: how we cut our build time from 9 minutes to 2. #DevOps #BuildInPublic",
       "thread": [
         "The biggest win was caching dependencies between runs, not faster machines.",
         "The second was running the slow tests only when their folder changed."
       ],
       "first_comment": "Listen: {{ $json.link }}"
     } },
     "media": [
       { "url": "{{ $json.cover }}", "type": "image", "alt": "Episode 42 cover: a stopwatch at 2:00" }
     ],
     "idempotency_key": "{{ $json.guid }}"
   }

8. Read the result, or schedule it

   The result carries the toot's link on your server and, for a thread, every post's id. To publish later, use Post → Schedule with When: At a Specific Time or In the Next Free Queue Slot (or POST /api/schedule with run_at). To react when a post lands or fails, start a second workflow with the PostWire Trigger node.

Every reply of a thread is sent with its own Idempotency-Key, made of the first post's id and its place in the chain, so a retry never leaves a second copy of a reply on your server. A whole workflow, from the trigger to the post, is laid out in n8n social media automation.