RipGuide
Caption and title limits on TikTok, YouTube, Instagram, Facebook, Threads and X
Updated
In short: TikTok 2,200 (UTF-16 runes, through the API), YouTube title 100 characters and description 5,000 bytes, Instagram 2,200 characters, Threads 500, X 280 with a weighted count. Facebook's Reels page states no limit. The unit matters as much as the number: YouTube counts bytes, Threads counts emoji as bytes, and X counts an emoji as 2. Every figure below is from the network's own page, read on 18 October 2026.
The limits
| Network and field | Limit | How it is counted | Source |
|---|---|---|---|
| TikTok caption | 2,200 through the API. In the app: not stated. | UTF-16 runes. | TikTok developers |
| TikTok hashtags | Not stated. | Hashtags sit inside the caption and count toward it. | TikTok developers |
| YouTube title | 100 characters. No < or >. | Characters. | YouTube Data API |
| YouTube description | 5,000 bytes. | Bytes, not characters. No < or >. | YouTube Data API |
| YouTube tags | 500 characters in total. | Commas count. A tag with a space counts as if wrapped in quotes. | YouTube Data API |
| YouTube hashtags | Three show above the title. More than 60 and all are ignored. | By number of hashtags. | YouTube Help |
| Instagram caption | 2,200, with 20 @mentions. Hashtags: Instagram's Help Center now says up to 5 a post (Instagram help, read in a browser 18 October 2026); the API reference still says 30. | Characters. | Meta developers |
| Facebook Reels description | No limit stated. The field "supports hashtags". | Not stated. | Meta developers |
| Threads text | 500, one topic tag, five links at most. | Characters, but an emoji counts as its number of UTF-8 bytes. | Meta developers |
| X post | 280. | Weighted: most Latin letters 1, emoji and CJK characters 2, any link 23. | X developers |
Characters, bytes and runes
Most limits are described in characters, which is what you see when you type. Three networks use something else, and a caption can pass a limit that looks safe.
- YouTube counts bytes in the description. YouTube's API reference says 5,000 bytes, not characters. In UTF-8, a plain English letter is one byte, a letter with an accent is usually two, most Chinese, Japanese and Korean characters are three, and most emoji are four. So 5,000 bytes is about 5,000 English letters, about 1,666 CJK characters or about 1,250 emoji. That is arithmetic on the standard encoding, not a number YouTube prints.
- Threads counts emoji as bytes. Meta's page says the 500 limit counts an emoji as its number of UTF-8 bytes. Most emoji are four bytes, so a caption with ten emoji uses about 40 of the 500. The page lists the 500 limit for text posts and gives no separate text limit for video posts.
- X weights characters. The 280 limit is a weighted count. Most Latin letters, punctuation and common symbols count 1. Emoji count 2, including ones with skin tone modifiers or joined by zero-width joiners (the joiners add nothing). CJK characters count 2. Any link counts 23, however long it is. X recommends its open-source twitter-text library for counting.
- TikTok counts "UTF-16 runes". That is TikTok's phrase in its developer docs, and the page doesn't define it further. In UTF-16 a plain letter is one unit and many emoji are two, so leave room if your caption has emoji. The 2,200 figure is the API limit. We found no TikTok page that states a limit for typing a caption in the app, though some guides quote 4,000.
What the pages do not say
- TikTok's hashtag limit. Not stated.
- Facebook Reels caption length. Meta's Reels publishing page lists a description and a title field and states no maximum for either. Don't trust a blog number for it.
- An X limit for Premium. The counting page we read doesn't give one, so we don't list a figure.
- Where each app cuts a long caption off in the feed. None of these pages say.
Writing one caption for several networks
- Write for the tightest network you use. If X is in the list, the first version fits 280 weighted characters, with a link counted as 23.
- Write the YouTube title separately. Keep it to 100 characters and leave out the < and > characters.
- Count YouTube's description in bytes if it has emoji or non-Latin text. Trim earlier than you think you need to.
- Set hashtags per network. Instagram allows 30, YouTube shows three above the title and ignores all of them past 60, Threads allows one topic tag, TikTok states no limit.
- Check the longest caption in the network's own composer before you schedule, because a tool can count differently from the app.
Video limits for the same networks are in the video specs cheat sheet, and each network has its own page: TikTok, YouTube Shorts, Instagram Reels.
How to do it in RipClip
RipClip has one calendar for TikTok, YouTube, Instagram, Facebook, Threads and X, and each post has its own caption and title per platform, so you can keep a short version for X and a long one for Instagram. Paid plans add an AI title, post caption and hashtags per clip, which you can edit before you schedule. Check each caption against the table above; the limits are the networks' and they change.
Posting switches on platform by platform as each platform approves RipClip; until then, download your clips and post them yourself. Captions on the video itself, the words on screen, are a different thing: see word-by-word captions. For posting one clip to three networks, see posting clips to TikTok, Shorts and Reels.