Free Bluesky Caption Generator

Graphemes, custom feeds, and what they change

Two things distinguish writing for Bluesky. The limit is 300 graphemes rather than characters, meaning a complex emoji or a non Latin character counts as one perceived symbol rather than several code points, which makes the effective space more predictable than on platforms using raw character counts. And discovery runs through custom feeds that users build and subscribe to, many of them topic based. Together these mean you have a little more room than the number suggests, and being clearly about a subject is what gets you into the feeds where people are looking.

How to write for Bluesky

The platform culture is still forming but some things already hold.

• Be clearly about something. Custom feeds are frequently topic based, and a post that could be about anything gets aggregated by nothing.
• Keep the tone informal. Bluesky skews conversational and reacts badly to posts that read as corporate announcements.
• Use the 300 graphemes rather than writing an X length post, since you have more room than the platform it is usually compared with.
• Add one or two topic tags to feed into custom feeds, but remember they count toward your limit.
• Reply to people. The default feed is chronological from accounts you follow, so conversation is a large part of how anyone sees you.
• Do not import an X posting strategy wholesale, since the audience and the norms genuinely differ.

How discovery works here

Bluesky sits between the algorithmic and fediverse models, which is unusual and worth understanding.

• The default feed is chronological from people you follow, so nothing is pushed to strangers there.
• Custom feeds are built by users and subscribed to deliberately, which is the main discovery layer.
• Anyone can build a feed, including you, so the discovery infrastructure is genuinely open rather than platform controlled.
• Some feeds aggregate by hashtag, some by keyword, some by author list, so tagging helps with a subset.
• Because feeds are opt in, audiences reached through them are smaller but considerably more interested.

Who uses this tool

Mostly people rebuilding an audience deliberately.

• People who left X and are establishing a presence somewhere with different norms.
• Journalists and writers, who are well represented among active accounts.
• Developers and technical users drawn by the open protocol underneath.
• Organisations using domain handles who need posts matching that credibility.
• Anyone whose posts reach their followers and never travel beyond them.

Bluesky post specs

The limits and how discovery is structured.

Bluesky is developing quickly and its conventions are less settled than older platforms, so verify specifics before relying on them. Checked September 2026.

When this is not the right tool

Bluesky is a smaller network than the platforms it gets compared with, so even good posting produces smaller numbers and reading that as failure would be a mistake. The default feed is also chronological, which means posting into an audience that is currently asleep genuinely reaches fewer people, in a way an algorithmic feed would smooth over. For the tags that feed custom feeds, use the Bluesky hashtag generator, and to check your draft against the grapheme count, the character counter measures it correctly.