Social Media Character Limits: A Plain Guide to the Main Networks

Why limits differ

Each network sets its own limits for posts, captions, titles and descriptions, and the numbers reflect how the platform wants text to look. A short limit pushes writers to make one point per post. A long limit suits articles and captions that tell a story. Networks also count in different ways, so the same text can pass on one platform and fail on another.

The figures below are those published or widely documented at the time of writing. Platforms change them from time to time, so treat the list as a planning guide and check the composer before you publish something important.

X, Bluesky and Threads

X allows 280 characters in a standard post, counted with weights: links count as 23 and emoji and Japanese, Chinese and Korean characters count as 2. Bluesky allows 300 characters per post. Threads allows 500 characters per post in its app, and the interface for developers counts that limit in bytes, which means an emoji uses four.

These three are built for short text, and the differences are small. If you cross-post, write for the shortest limit and expand where you can. A post that fits into 280 characters fits everywhere.

Facebook and TikTok

Facebook is the outlier: a post is widely quoted at 63,206 characters, a figure that is not officially documented, and the feed folds long text after a few lines. TikTok raised its caption limit from 2,200 to 4,000 characters, with a bio of 80 characters, though older app versions may still stop at 2,200.

Neither limit is the real constraint. Only the first lines of a Facebook post or TikTok caption are visible before the text is expanded, so write for those lines first.

Instagram

An Instagram caption can hold up to 2,200 characters. Only the first lines are shown before a “more” link, and the commonly quoted figure is about 125 characters, so the opening words do most of the work. A profile bio is limited to 150 characters and a username to 30.

Hashtags count as part of the caption. Instagram has allowed up to 30 hashtags in a post, though a handful of relevant ones is the usual advice, and the rules can change. Put the key message and any call to action before the cut-off.

LinkedIn

A LinkedIn post can hold up to 3,000 characters, which is room for a short article. As on Instagram, the feed shows only the first few lines, then a “see more” link, so the first sentence must earn the click. Headlines for articles, names and job titles have their own, shorter limits that are shown in the editor.

Because the limit is generous, the risk on LinkedIn is not running out of space but writing text that is too long to read. Short paragraphs of one or two sentences, separated by a blank line, are easier to read on a phone.

YouTube

A YouTube video title can contain up to 100 characters, and a description up to 5,000, according to YouTube’s help pages. Only the first part of a title appears in search results and on phones, so put the important words first. The description shows a few lines before “more”, so use that space for the main point and any links.

Both fields reject some characters, so a title copied from another application can fail even when it is under 100. Retyping the unusual characters usually solves it.

Search and advertising limits

Search engines and ad systems also have limits. A responsive search ad on Google needs headlines of up to 30 characters and descriptions of up to 90, and Google counts double-width characters such as Japanese, Chinese and Korean as 2 each. A page title and meta description are not limited by a fixed rule but are cut by display width, so about 60 and 160 characters are the usual guides.

These limits matter for money as well as style. An ad that is over the limit is not accepted, and a title that is too long is cut where the reader most needs it.

Counting differences between networks

Networks do not count in the same way. X applies weights, so links count as 23 and emoji as 2. Some interfaces for developers count bytes or UTF-16 units instead of visible characters, so a single emoji can use two to four places in the limit. A counter that counts visible characters will therefore sometimes show fewer characters than the platform does.

For that reason, leave a margin of about five to ten per cent when your text contains emoji, links or non-Latin scripts, and make the last check in the composer of the network itself.

Which limit is the strictest

If you publish the same message on several networks, the strictest limit decides the shortest version. For short posts that is X at 280. For titles it is a YouTube title at 100, and for ads it is a Google Ads headline at 30. Write the short version first and expand it for the networks that allow more.

Do not simply cut a long text down for a short platform. A message that has been shortened mechanically often loses its point, and a rewrite from the main idea is almost always clearer.

A routine for cross-posting

1. Write the core message in under 280 characters.
2. Check it in the counter with the X limit selected and leave a margin for links and emoji.
3. Expand it for Instagram or LinkedIn, and place the key point in the first 125 characters.
4. Rewrite the title for YouTube or your own page with the main words first.
5. Paste each version into its platform and confirm it is accepted.

The routine keeps your message consistent and stops you from shortening a text at the last minute. If a limit changes, update only the step that uses it.