There was a time when stacking thirty hashtags under an Instagram post was enough to gain visibility. That era is over — but the opposite conclusion, "hashtags are pointless now", is just as wrong. Their role has simply shifted.

What changed

Social networks moved from distribution based on follows and keywords to distribution based on estimated interest. Today, an algorithm analyses the content directly — image, text, audio — to infer the subject, without needing to be told.

Hashtags therefore lost their primary signalling function. They keep two uses: explicit categorisation when content is ambiguous, and community navigation when users actively follow a tag.

Instagram: fewer, but better

Instagram still allows thirty hashtags, but the platform itself has indicated that three to five is enough. Many accounts' experience points the same way: beyond that the effect is nil, even slightly negative — a list of thirty tags reads as amateurish.

What still works: precise hashtags that genuinely describe the content. A tag followed by fifty thousand accounts exposes you to an identifiable community. A tag followed by fifty million buries you in three seconds.

What no longer works: copy-pasted lists reused across posts, generic tags like #love or #instagood, and unrelated tags added to widen reach.

LinkedIn: three maximum

LinkedIn is where excess is most noticeable. Three hashtags is the norm, and past five a post takes on a promotional look that works against you in a professional feed.

Their usefulness is real but specific: LinkedIn lets you follow a hashtag, and some professional communities do organise around a few sector tags. In that case, the hashtag places your post into a monitored stream.

Outside those actively followed niche tags, the contribution is marginal.

TikTok: categorise, don't chase rankings

On TikTok, hashtags help the algorithm place a video during its first distribution, when it still has few behavioural signals. After that initial test, retention and interaction decide.

Three to five precise hashtags describing subject and format fill that role. Tags like #fyp or #viral have no demonstrated effect: they're used on billions of videos and carry no information.

Pinterest: the special case

Pinterest went the other way and has progressively removed hashtags from how it works. The platform behaves like a search engine: the title and description, in natural language, determine how a pin ranks.

Writing a description that genuinely explains what the pin shows, using the words someone would search with, has far more effect than any list of tags.

The method that still holds

An effective selection mixes three levels:

  • One or two broad tags, for the general category.
  • Two or three niche tags, precise, describing your exact angle.
  • One brand tag, your own, to group your posts and track what your community publishes.

Vary this selection between posts rather than pasting the same list. Systematic repetition adds nothing and can read as automated behaviour.

A test to run yourself

Post for three weeks with your usual selection. Then three weeks with five precise hashtags, chosen one by one. Compare the share of reach coming from non-followers.

That's the only metric that genuinely answers the question, because it isolates what hashtags are supposed to produce: exposure outside your existing audience. On many accounts the gap is smaller than expected — and that's useful information in itself.

What to take away

  • Instagram: three to five precise hashtags, never thirty.
  • LinkedIn: three maximum, useful only if the community follows the tag.
  • TikTok: three to five descriptive tags; forget #fyp.
  • Pinterest: natural-language descriptions matter far more.
  • One niche tag beats ten popular ones.