How BlueSky Hashtags Work (and How to Use Them)

If you've spent time on older social platforms, you probably have some muscle memory around hashtags: pile on five or ten, hope one of them gets picked up by a search, and move on. BlueSky works a little differently, and a lot of the old habits either don't help or quietly work against you.

This is a plain walkthrough of how hashtags actually function on BlueSky, where they help, where they don't, and a few simple habits worth keeping. No tricks, no magic number of tags that unlocks the algorithm. Just how the thing works.

What a hashtag actually does on BlueSky

A hashtag on BlueSky is a clickable tag. When you put a # in front of a word, it becomes a link, and tapping it takes you to a feed of recent posts using that same tag. That's the core function: a hashtag is a way to group posts around a topic so people can find them by browsing or searching the tag.

BlueSky is built on the open AT Protocol, which means the network is a shared, open set of data rather than a single closed app. Tags are stored as part of the post's structure, so they're searchable across the network rather than tied to one company's internal index. The practical upshot for you is simple: a tag is a label that helps people and feeds find your post by topic. It is not a paid boost, and it doesn't guarantee reach.

Hashtags are common, but not expected on every post

One of the bigger cultural differences on BlueSky is that most posts don't use hashtags at all. They work fine and plenty of people use them, but they're a minority of posts rather than the default. Nobody expects every post to carry a row of tags, and a post with none looks completely normal.

That changes how you should think about them. Instead of asking 'how many tags should I add,' ask 'is there a tag here that genuinely describes what this post is about and that someone might actually browse.' If the answer is no, skipping them entirely is a perfectly good choice.

When hashtags are worth using

Hashtags earn their place when there's a real community or recurring topic behind the tag. A few situations where they tend to help:

Active community tags, where people actually click through to browse, like tags around a hobby, a fandom, or a profession.

Recurring events or themes, where a regular tag collects everyone's posts in one place over time.

Niche topics you want to be findable for, where a specific tag is more useful than a broad one.

Art, photography, and other visual work, where browsing a tag is a normal way people discover new accounts.

In all of these, the tag is doing honest work: it's connecting your post to a group of people who are looking for exactly that. That's the test. If a tag links your post to a real audience, keep it. If it's just decoration, drop it.

Habits that keep your tags useful

A handful of small habits go a long way. None of these are rules so much as defaults that tend to read well:

Keep it to one or two tags. A wall of hashtags reads as spammy and rarely adds reach on BlueSky.

Be specific over broad. A focused tag reaches the people who care; a giant generic tag mostly gets buried.

Put tags where they read naturally, either woven into the sentence or grouped at the end, not scattered mid-thought.

Use real words. Tags can't contain spaces, so use CamelCase for multi-word tags to keep them readable, like #BookRecommendations.

Watch your length. Tags count toward the post's character limit, which matters more than it sounds.

That last point trips people up. BlueSky posts cap at 300 characters, and every character in a hashtag counts against that limit. A few long tags can eat the space you needed for the actual thought. If you're regularly bumping against the cap, it helps to see your count as you write.

a BlueSky character counterso you can see exactly how much room your tags are leaving.

Finding tags worth using

The best way to pick tags is to watch what your own community already uses. Before you invent a tag, search for it and see whether anyone's posting under it. A tag with a steady stream of recent posts is a real community; a tag with nothing is just a label only you can see.

If you want a starting point for a given topic, a generator can surface tag ideas you can then sanity-check by searching them on BlueSky. Treat its output as suggestions, not gospel, and only keep the ones that map to real activity.

a hashtag generator built for BlueSkyuseful for ideas you then verify by searching the tag.

A reasonable approach

Hashtags on BlueSky are a quiet, optional tool rather than a growth lever. They help most when they connect a specific post to a specific community that's actually browsing. They help least when they're added out of habit, in bulk, hoping something sticks. There's no paid verification or boost behind them, and no count that games reach, so the honest version is also the effective one: use a tag when it describes a real topic people search, and skip it otherwise.

If you're planning posts ahead of time, it's worth deciding tags as you write rather than tacking them on at the end, since they affect both your character budget and your tone. Tools like ONYX can help you draft and schedule BlueSky posts in one place, but the underlying habit matters more than any tool: write the post first, then add a tag only if it earns its spot.

try ONYX's free BlueSky post generatora no-signup way to draft a post and see how tags fit.