What is the character limit for a TikTok caption?

Short answer

TikTok’s Help Center gives no character limit for a caption. Its developer documentation does: a video post’s caption can be 2,200 characters through the Content Posting API, and a photo post takes a 90-character title and a 4,000-character description. Hashtags and mentions are part of the caption, with no separate figure. Numbers quoted for the app, such as 4,000, are not on a TikTok help page we could read, so we don’t give them as TikTok’s.

Written by the Mellow team · Updated October 10, 2026, sources read October 10, 2026

What TikTok publishes

Read on 10 October 2026:

Where	Figure	Source
The app and its Help Center	No caption limit is given. The page on making a post lists “Add description” and “Add hashtags” and no number	TikTok Help Center
Video post through the API	2,200 UTF-16 runes for the caption	Direct Post reference
Photo post through the API	Title 90, description 4,000 UTF-16 runes; up to 35 photos	Photo post reference
Mentions	No limit is given	TikTok Help Center
Bio	80 characters	TikTok Help Center
Account name	30 characters	TikTok Help Center

The API reference says hashtags (#) and mentions (@) are matched in the caption, delimited by spaces or new lines. It sets no limit of their own, so they count toward the caption.

Why we don’t give a number for the app

A figure for captions typed in the app is easy to find. It isn’t on a TikTok help page, and pages on tiktok.com generated from search results quote different numbers on the same page, so they are not a source. TikTok’s help describes the caption field and its hashtags and mentions without a count. If TikTok publishes one, this page changes.

Characters, runes and emoji

TikTok’s API states the limit in UTF-16 runes. In UTF-16 most emoji take two units, so a caption heavy with emoji is longer to TikTok than it looks. Mellow Hub counts a TikTok caption by its UTF-16 length, so an emoji counts as 2 there too; TikTok doesn’t document how it counts a joined emoji.

Captions in TikTok ads

For ads TikTok does give numbers. On its page for reservation in-feed ads: a Spark Ads caption is pulled from the organic video and supports up to 150 characters or none; for other ads TikTok suggests keeping a caption within 50 characters for Chinese, Japanese and Korean or 100 characters in other languages, so “See more” doesn’t cover it, and shows at most 4 lines. The video ad specifications say the same of lines.

Posting TikTok captions with Mellow Hub

Hub checks a TikTok caption against 2,200 characters and a photo post’s title against 90. It uses the smaller caption figure for photo posts too, so one caption goes to either. A caption over the limit is cut at the last paragraph, line or sentence that fits, and the post’s notes say so. The same post can carry a different caption for each network.

Hub is paid: plans start at $19 a month (Solo), after a 7-day trial with a card on file that costs nothing if you cancel before it ends, and a monthly plan's first month is 20% off. Publishing is unlimited on every plan, under a fair-use ceiling that stops automated floods (900 publications a month on Solo). One publication is one post on one account, so a post sent to five networks counts as five. There are no automatic overage charges.

Questions people also ask

What is TikTok’s caption limit in the app?

TikTok’s Help Center gives no figure, and we don’t state one that isn’t on a TikTok page. The numbers TikTok does publish are for its API: 2,200 for a video’s caption, and a title of 90 and a description of 4,000 for a photo post.

How many hashtags can a TikTok caption have?

TikTok’s help and its API reference give no number. Hashtags are part of the caption, so they count toward its limit.

How long should a TikTok ad caption be?

For in-feed ads TikTok suggests keeping a caption within 100 characters, or 50 for Chinese, Japanese and Korean, so “See more” doesn’t cover it. A Spark Ads caption supports up to 150 characters, and at most 4 lines are shown.

How long can a TikTok bio be?

80 characters, according to TikTok’s Help Center page on changing your bio, which describes the web version. Account names can be up to 30 characters.

Why does a scheduling tool refuse my TikTok caption?

Scheduling tools post through TikTok’s API, which takes up to 2,200 characters for a video’s caption. A caption longer than that has to be cut, or posted from the TikTok app.

Sources

Other companies’ features change. Every statement about them rests on these pages, as they read on the date above.