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Enter what your video is about and get ready-to-post captions: a first line people read before "more", a call to action and hashtags for the topic.
These are post captions: the text under your video, whose first line is what people read before tapping "more". The words on screen are subtitles, which ShortFast burns into every video it makes.
Type what your TikTok is about and pick a tone: casual, educational, funny, story or business. The generator writes 9 captions, each with the three parts a TikTok caption needs: a first line that makes people tap "more", a second line that gives them a reason to watch to the end, and a call to action that asks for the comment, save or follow you want.
Hashtags are built from your topic, the whole phrase as one tag and its key words as others, plus one or two the tone usually carries, five at most. Turn them off if you prefer to add your own. Generate again for new combinations, then copy the caption you like straight into TikTok.
How it works
Enter the topic in a few words, such as "meal prep for students" or "budget travel in Japan".
Choose one or more tones, or leave them all on to compare. Business captions end with a link-in-bio or comment-for-guide call to action.
Leave hashtags on for topic tags, or switch them off and add your own.
Copy the caption into TikTok when you post. Read the first line on its own: it's the part most people see.
On TikTok the caption is the text under the video, not the words on screen. It tells TikTok and viewers what the video is about, and its first line is the only part most people read before tapping "more". A first line that adds something the video doesn't say (a promise, a question, a reason to watch to the end) does more than one that repeats it.
The rest of the caption is for the people who are already interested: a short reason to stay and a single, clear ask. Asking for one thing works better than asking for everything, so each caption here ends with one call to action: a save, a comment or a follow.
A few specific hashtags beat a wall of generic ones. Tags that describe the topic help TikTok understand the video and help people who search or browse that topic find it. Broad tags shared by millions of videos add little. That's why the generator uses your topic for most tags and stops at five.
Hashtags support a caption; they don't replace one. A caption that clearly says what the video is about, in the words people search for, does a lot of the same work.
Channels that grow on TikTok usually post often, and writing a fresh caption for every video adds up. ShortFast writes the script, voiceover, captions and post text for each video it makes, and can publish to TikTok, YouTube Shorts and Instagram Reels on a schedule, so every post goes out with its own caption.
FAQ
Keep going
Openers for the first two seconds of the video itself.
OpenFree toolTitles for the same video on YouTube Shorts.
OpenFree toolCheck that your TikTok handle is free before you claim it.
OpenFeatureThe words on screen: burned into every ShortFast video.
OpenPlatformHow ShortFast generates and posts TikToks on a schedule.
OpenShortFast writes the script, generates the video, adds captions, and posts it to TikTok, Reels, and YouTube Shorts for you, every day.
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