TikTok Caption Character Limit: App vs API
Blog / SOCIAL MEDIA
TikTok documents a 2,200 UTF-16-rune limit for video captions through its Direct Post API. Its photo-post API separately allows a 4,000 UTF-16-rune description and a 90-rune title. These documented API limits do not establish a universal caption limit for every version of the TikTok app.
Identify the type of post
The video API calls its caption field title, while the photo API provides separate title and description fields. Similar labels in publishing tools can therefore refer to different limits.
A pottery demonstration uploaded as a video and a photo collection showing the finished pieces do not necessarily share the same text budget. Match your draft to the specific content format.
Treat in-app claims cautiously
You may encounter claims that all TikTok captions allow 4,000 characters. The official API documentation supports that figure for a photo description, but not for its video-caption field.
If you publish manually, inspect the description field in your own app. If you publish through another service, check that service's validation rather than assuming the app and API behave identically.
Budget for the complete caption
TikTok's video API describes hashtags and mentions as part of the caption text. Keep them in the draft when assessing whether the complete submission fits.
For a bike-repair clip, write the useful instruction first: 'Check the tire sidewall before inflating.' Add a relevant mention or hashtag afterward, then validate the resulting caption instead of measuring only the opening sentence.
Leave Unicode validation to the destination
The developer references express their limits in UTF-16 runes. A visible symbol is not always a single unit in a text encoding, so an ordinary visual count can be misleading for emoji-heavy captions.
Use the character counter for drafting, but regard the app or publishing integration as the final acceptance check. If counts disagree, simplify decorative symbols and inspect the exact text sent to TikTok.
Frequently asked questions
Is TikTok's caption limit 2,200 or 4,000?
The documented API limit is 2,200 UTF-16 runes for a video caption and 4,000 for a photo description. Do not generalize either to every app workflow.
Do hashtags use the video caption budget?
Yes. The video API places hashtags and mentions within the caption field.
Is the photo title included in its description limit?
The API documents separate fields: a 90-rune photo title and a 4,000-rune description.