# Video Subtitle Burner > Free tool to add subtitles to video: AI auto captions on your device, burn SRT/VTT into MP4, edit captions and style them with TikTok-style word highlight. No upload, no watermark. Add captions to any video and burn them into the picture. Generate them automatically with AI speech recognition that runs on your own device, import an SRT or VTT file, paste a transcript to auto-time it, or type captions while the video plays. Style them with presets such as YouTube, TikTok bold, karaoke and lower third, including word-by-word highlighting, then export an MP4 with open captions plus SRT/VTT files. - **Live tool:** https://www.toolnova.org/video-tools/video-subtitle-burner - **Category:** Video Tools (https://www.toolnova.org/video-tools) - **Price:** Free - **Requirements:** Runs in a modern web browser · No signup · No install ## What this tool does - AI auto captions (Whisper) with word-level timing, run on your device - Import SRT and VTT, export SRT and VTT - Paste a transcript and auto-time it into short captions - Caption editor: set in/out from the playhead, jump, duplicate, delete - Shift all captions to fix sync - 6 style presets: Classic, YouTube, TikTok bold, Karaoke, Cinema, Lower third - Word-by-word (karaoke) highlight - Fonts, size, colors, outline, box, shadow, uppercase - Top, middle or bottom placement with offset - MP4 or WebM with burned-in captions, faster than real time ## How to use Video Subtitle Burner 1. **Upload your video** — Drop the MP4, MOV or WebM you want to caption. 2. **Add captions** — Import an SRT/VTT, paste a transcript to auto-time it, or add captions at the playhead. 3. **Fine-tune timing** — Edit start/end times, use the now buttons or shift all captions to sync. 4. **Style them** — Choose a preset, then adjust font, colors, outline, box, position and word highlight. 5. **Burn and download** — Click Burn captions into video; optionally download the SRT or VTT too. ## Common use cases - Add TikTok-style animated captions to Reels and Shorts - Hardcode SRT subtitles into an MP4 for social platforms - Caption tutorials and lectures for accessibility - Create karaoke and lyric videos - Make translated versions with a subtitle file - Turn a script into timed captions in seconds ## About ### Automatic captions with on-device AI Click Auto captions (AI) and the speech in your video is transcribed by Whisper, an open speech-recognition model, running inside your browser. The model is downloaded once (about 41 MB for Fast, 77 MB for Accurate) and cached; your audio is never uploaded. It supports 17+ languages, records the timing of every word for perfectly synced karaoke highlighting, and splits the text into short, readable captions you can then correct. ### Other ways to add captions Already have a subtitle file? Import the SRT or VTT and the captions appear on the timeline instantly. Have a script or transcript? Paste it and choose how many words per caption; the text is split into short lines and spread across the video, ready for small timing tweaks. Starting from scratch? Play the video and press Add at each line, then use the now buttons to set the start and end from the playhead. ### Caption styles that get watched Most social video is watched without sound, so readable captions increase watch time. Pick a preset as a starting point and adjust any detail. | Preset | Look | Best for | | --- | --- | --- | | Classic | White text, black outline | Any video, films, tutorials | | YouTube | White text on a dark box | Long-form and educational content | | TikTok bold | Big uppercase, centered, word highlight | TikTok, Reels, Shorts | | Karaoke | Words light up as they are spoken | Music, lyrics, language learning | | Cinema | Serif font with soft shadow | Short films, documentaries | | Lower third | Colored bar, uppercase | News-style quotes and interviews | ### Word-by-word highlighting Turn on Word-by-word highlight and each caption's words change color one after another across the caption's duration, with the current word slightly enlarged: the dynamic caption style popular on TikTok and Reels. Choose any highlight color, and use the UPPERCASE and outline settings for maximum punch. ### Burned-in vs. subtitle files Burned-in (open) captions are part of the picture, so they appear on Instagram, TikTok, WhatsApp, LinkedIn and anywhere else, exactly as styled, but they cannot be turned off. Subtitle files (closed captions) can be switched on and off and translated, and are what YouTube and video players prefer. This tool gives you both: export the video with burned-in captions and download the same captions as SRT or VTT. ### Fix out-of-sync subtitles If an imported SRT is consistently early or late, use Sync: shift all captions to move every caption by up to ±5 seconds in 0.05 s steps, then Apply. Individual captions can be adjusted with the number fields or the now buttons. See also: [Resize the captioned video for Reels and TikTok](https://www.toolnova.org/video-tools/video-resizer), [Add your logo watermark](https://www.toolnova.org/video-tools/video-watermark), [Make a thumbnail](https://www.toolnova.org/video-tools/video-thumbnail-maker) ## FAQ ### How do I burn an SRT file into a video? Load the video, click Import SRT / VTT, choose a style and click Burn captions into video. The captions become part of the picture in the exported MP4. ### Can it generate captions automatically? Yes. Auto captions (AI) transcribes the speech with Whisper running on your device, with word-level timing, in 17+ languages. Nothing is uploaded. ### Can I make captions without a subtitle file? Yes. Use Auto captions (AI), paste a script to auto-time it, or add captions one by one while the video plays. ### How do I get TikTok-style captions? Choose the TikTok bold preset, which uses big uppercase text with an outline and word-by-word highlighting. You can change the highlight color. ### My subtitles are out of sync. How do I fix them? Use Sync: shift all captions to move every caption earlier or later, then click Apply. You can also edit individual start and end times. ### Can I download the captions as an SRT file? Yes. Export SRT or VTT at any time; these files work on YouTube and in most video players. ### What is the difference between burned-in and soft subtitles? Burned-in captions are drawn into the video and always visible on every platform. Soft subtitles are a separate file that viewers can switch on or off. ### Is my video uploaded? No. The captions are drawn and the video encoded in your browser. --- ToolNova — free, privacy-first browser tools. Most tools process data locally on your device. See https://www.toolnova.org/llms.txt for the full directory.