A Mastodon scheduler that respects your instance.
Connect any Mastodon server, keep your content warnings and alt text, and queue posts next to the rest of your channels. If a post cannot go out, you hear about it first.
Shipped per-channel retries with backoff. If a network is down we stop, tell you, and try again.
- Bluesky09:00:02posted
- Mastodon09:00:03posted
- LinkedIn09:00:04posting
- Threadswarned Mon 17:40reconnect
Mastodon scheduling
Why schedule Mastodon
The fediverse spans every time zone, and most Mastodon apps have no queue. Scheduling lets you post when your followers are awake without being online yourself.
SyncPoster signs in with standard OAuth on your own instance, reads that instance's real character limit, and posts through the official API.
How it works
Scheduling Mastodon in three steps.
- 01
Enter your instance
Type your server address, approve access on your own instance, and you are back in SyncPoster.
- 02
Write with fediverse manners
Add a content warning for Mastodon only, describe your images, and send the same post to your other channels.
- 03
Know the moment it matters
Each channel reports its own state. A 429 or a 5xx retries with backoff; an expired token stops and tells you, ahead of the time the post was due.
Honest notes
What it does, and what it does not.
Better to know now than after you have paid.
Supported
- Any Mastodon-compatible instance
- Content warnings, set per post
- Up to four media attachments with alt text
- Your instance's own character limit, read from the server
Not yet
- Polls
- Threads of several posts (single posts only for now)
- Boosting or replying on your behalf
| Limit | Value | Source |
|---|---|---|
| Post length | Your instance's limit, 500 by default | Read from the instance by our Mastodon adapter |
| Media per post | 4 | Enforced by our Mastodon adapter |
| Media uploads | 30 per 30 minutes per user | Mastodon API rate limit, retried when hit |
Agent-native
Let your assistant schedule Mastodon.
The MCP server and REST API come with every plan, so the same queue works from a chat window.
you Queue my release notes to Mastodon at 17:00 with the content warning "long post". tool syncposter.schedule_post mastodon scheduled
Questions
Mastodon scheduling FAQ
Does it work with my instance?
Yes, if it speaks the Mastodon API. You enter the server address and approve access there, so your instance stays in control.
Can I add a content warning on Mastodon only?
Yes. The content warning is a Mastodon-specific field on the post, so your other channels are not affected.
What if my instance allows more than 500 characters?
SyncPoster reads the limit from your server, so longer posts are allowed wherever your instance allows them.
What if my instance is down at posting time?
Server errors and rate limits retry with backoff, up to five attempts. If it still fails, Mastodon shows failed with the reason and the rest of your channels are unaffected.
Also on SyncPoster
The rest of your queue.
Schedule Mastodon the calm way.
Connect your channels, queue a week of posts, and let SyncPoster tell you if anything needs you.