- How do I add subtitles to a video online for free without a watermark?
- Use this tool: upload your video and a .srt subtitle file, set the style you want, and click Burn Subtitles. The download has no watermark, no logo, and no branding of any kind. The tool is free because all processing happens in your browser using FFmpeg.wasm — there is no server to pay for.
- What is the difference between hard subtitles and soft subtitles?
- Soft subtitles (also called external or embedded subtitles) are stored as a separate text track. The viewer can turn them on or off, but not all players support them. Hard subtitles (burned-in or hardcoded subtitles) are permanently drawn onto the video frames. They work on every device and platform — YouTube, Instagram, WhatsApp, smart TVs — with no extra files needed. This tool creates hard subtitles.
- What subtitle file formats are supported?
- This tool accepts .srt (SubRip Text — the most common format, used by YouTube, VLC, and most video editors), .vtt (WebVTT — used by HTML5 video and web platforms), and .ass / .ssa (Advanced SubStation Alpha — supports advanced styling). You can also paste SRT content directly into the text box without uploading a file.
- Why is processing slow on large videos?
- FFmpeg.wasm re-encodes the entire video to draw subtitles into every frame where they appear. A 10-minute HD video may take 5–15 minutes depending on your device's CPU speed. For faster results, try a shorter clip or lower the input video resolution before uploading. The progress log updates in real time so you can see it working.
- Do my video files get uploaded to a server?
- No. FFmpeg.wasm is a WebAssembly build of the FFmpeg library that runs entirely inside your browser. Your video, subtitle file, and output are never sent to any server. You can even disconnect from the internet after the page loads and it will still work. This makes it suitable for personal, confidential, or copyrighted video content.
- What video formats can I use as input?
- MP4 (H.264, H.265), WebM (VP8, VP9), MOV (QuickTime), and MKV are all supported. The output is always MP4 for widest compatibility. If your video is in a rare codec, try converting it to MP4 first using a tool like HandBrake (free, offline).