Post to Mastodon from your Mac and iPhone
Post to any Mastodon instance, with the limit your instance sets.
Live Free for your first account
What PostOnly enforces for Mastodon
| Character limit | 500 |
|---|---|
| Images per post | 4 |
| Auto-threading | Yes, over-limit posts are split into a sequence of posts |
| Title field | No |
| Image required | No |
Image rules
- Up to 4 images per post
- Each image under 8 MB; PostOnly resizes to fit
Posting to Mastodon with PostOnly
PostOnly signs in to your own Mastodon instance, so it works with any server, not just mastodon.social. It registers itself as an app on that instance the first time you connect.
The character counter reads the limit from your instance. The 500 shown here is the common default, and a server that allows more gets more. Posts that run over become a reply thread.
How to connect Mastodon
- In PostOnly choose Add Account → Mastodon.
- Enter a display name and your instance's address (for example
mastodon.social). - Click Sign In. Your instance's login page opens in your browser.
- Approve PostOnly. You return to the app with the account connected.
Good to know
- Sign-in always happens on your instance's own page; PostOnly never sees your password.
- The character limit is per instance. PostOnly discovers it when you connect.