Click to choose a file or drag a video here
Output size
Captions are burned permanently into the picture — anyone can see them, no player support or subtitle track needed, which is why platforms like TikTok and Instagram expect captions this way. That also means they can't be turned off afterward. Up to 8 captions, each showing during its own time range only. "Social media" reformats to the standard 1080×1920 vertical frame TikTok/Reels/Shorts expect, filling the extra space with a softly blurred, scaled-up copy of your own video rather than cropping anything out — the same technique TikTok Video Editor uses. "Custom" keeps your video's original size and aspect ratio untouched. Runs on a real video engine loaded into your browser (FFmpeg, compiled to WebAssembly) — about 30MB, downloaded once and cached for the rest of this visit. Nothing is uploaded; the work happens on your device.
How it works
- Upload your video.
- Type in captions and set the timing for each line.
- Burn in the subtitles and export at original size or a social media format.
Frequently asked questions
Are subtitles burned into the video or a separate file?
They're burned directly into the video, so they show up everywhere it's played.
Can I export in a size made for social media?
Yes, choose original size or a social-media-ready format.
Can I set subtitle timing precisely?
Yes, set exact start and end timing for each caption line.
Your files are never uploaded. Gotool.xyz runs entirely as JavaScript in your browser. Your files are processed in memory and never touch a server — nothing to breach, nothing to clean up. Close the tab and it's like it never happened. The only thing we count is which tool ran (just the name, e.g. "merge") so we know what people find useful — never your file, its name, its size, or anything in it.