Add captions to any video
AI transcribes your video in the browser, you style the captions — word-by-word TikTok style, background box, size, position — and download an MP4 with them burned in. Nothing is uploaded.
Free · No signup · Files never leave your device
Drag and drop a video or audio file
or click to browse
How it works
Drop your video
Any MP4, MOV, MKV, or phone recording — it never leaves your device.
AI writes the captions
OpenAI's Whisper speech-recognition model transcribes the audio right in your browser, with timestamps for every caption.
Style and burn them in
Pick the caption style — word-by-word TikTok captions, background box, size, position — preview it live, and download an MP4 with the captions baked into the picture.
TikTok-style captions without an editor
Most viewers watch social video with the sound off, so captions aren't optional anymore — they're the difference between a scroll-past and a view. This tool adds them the way the big caption apps do, but without uploading your footage anywhere: OpenAI's Whisper speech-recognition model downloads to your browser once, transcribes the audio on your own hardware, and the captions are drawn permanently into the video frames — hardcoded, so they show identically on TikTok, Instagram Reels, YouTube Shorts, LinkedIn, and anywhere else.
The style controls cover the looks you actually see on social feeds. Show one word at a time for the punchy TikTok auto-caption effect, three-word phrases for a steadier rhythm, or a classic two-line subtitle layout. Put a solid box behind the text so it stays readable over busy footage, bump the size for phone screens, and choose bottom or center placement. The preview overlays your choices on the video player as it plays, so there are no surprises in the download — and re-styling doesn't re-transcribe, so trying different looks is instant.
Burned-in captions vs subtitle files
Burned-in captions are pixels: every platform and player shows them, but they can't be turned off. If you want a separate SRT or VTT file to upload alongside the video (YouTube, editing software) or a plain transcript, the same tool generates subtitle files too — or add them as a soft track that viewers can toggle. Already have subtitles? Upload your own SRT or VTT and skip straight to styling. For a smaller upload after burning, the video compressor shrinks the result, and the video trimmer cuts the clip down before you caption it.
Frequently asked questions
Yes. The caption maker is completely free, with no signup, watermarks, or usage limits. We make money from our video translation service, not from this tool.
No. Both the Whisper AI transcription and the video re-encode run locally in your browser. Your video never leaves your device — once the model has loaded, the tool even works offline.
You control how much text shows at a time (full sentences, a standard two-line maximum, short phrases, or one word at a time like TikTok auto-captions), the text size, a solid background box behind the text, and whether captions sit at the bottom or the center of the frame. A live preview on the video shows exactly what you will get.
Yes — that is what it is built for. The captions are burned permanently into the pixels, so they show up on every platform, including the ones that ignore subtitle files. Portrait 9:16 video is fully supported, and the word-by-word style matches the popular TikTok caption look.
Whisper was trained on about 100 languages, including English, Spanish, French, German, Chinese, Japanese, Arabic, and Hindi. Language is auto-detected by default. In browsers with hardware video acceleration (Chrome, Edge, Safari) every script renders correctly; in other browsers rendering works best for Latin, Cyrillic, and Greek alphabets.
The Whisper speech model (~77–150 MB depending on your browser) downloads the first time you use the tool and is cached by your browser. After that, transcription starts immediately.
The same tool does that too — after transcribing, switch to "Subtitle file" to download SRT, VTT, or a plain-text transcript, or "Soft track" to add a toggleable subtitle track without re-encoding. It accepts audio files as well.
Yes. Upload an existing SRT or VTT file and skip transcription — then burn those captions into the video, add them as a soft track, or convert them to another format.