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OpenPost
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Mastodon

Mastodon

OAuth 2.0 per instance

Publish to the Mastodon server your community already uses.

This page is for people deciding whether OpenPost fits their Mastodon publishing workflow.

Connect a public Mastodon server, then schedule posts, media, links, and reply threads.

Implemented: Publishing is implemented

Managed certification: No managed provider-format certification claim is current.

Try OpenPost Platform guide

Formats and limits

Different formats, different rules.

OpenPost checks the text and media rules for the format you choose.

Post, thread, or link

Text
500 characters by default
Media
Text only

Media post

Text
500 characters by default
Media
Up to 4 images, GIFs, or MP4 attachments

Provider limits and scope

  • 500 characters by default
  • Up to 4 attachments
  • Reply threads and OpenPost scheduling
  • Instance rules can override the defaults

Connect and test

Set up Mastodon in three checks.

  1. 1

    Choose Mastodon in Social accounts and enter the public server address.

  2. 2

    Approve the dynamically registered or operator-configured app on that server.

  3. 3

    Confirm the instance-specific text and media rules before scheduling.

Known limits

What can still block a post.

  • Character, attachment, and video limits can differ by server.
  • Custom instances must be public HTTPS and allow app registration.
  • One adapter registration is maintained per Mastodon instance.

Account requirement: An account on a public HTTPS Mastodon instance that allows app access.

Verification: Check the server rules and publish one media test before you rely on a new server.

Use the current callback address, permissions, and media setup.

Social network developer pages change. The OpenPost guide lists the settings and checks you need now.

Read the Mastodon guide