Add subtitles to videoの使い方
- 1
Drop the video and the subtitles
Add an MP4, MOV, MKV, WebM or AVI video together with its .srt or .vtt file, or drop them one after the other. The subtitles play over the preview straight away.
- 2
Check the timing
Scrub through the video; if every line comes too early or too late, nudge them all by half a second. Broken letters mean a different text encoding, which you can switch.
- 3
Burn in or add a track
Burn in draws the text into the picture for Instagram, TikTok or WhatsApp; Separate track adds subtitles viewers can turn on and off, without re-encoding.
- 4
Style burned-in captions
Choose the font, size, colour, a box, outline or shadow behind the text, and whether it sits at the top, middle or bottom.
- 5
Export
Download name-subtitled.mp4 for burned-in captions, or name-subtitles.mp4, .mkv or .webm with the new track.
制限と Pro
One video at a time, up to 500 MB and 10 minutes, with any number of subtitle lines and no watermark.
Pro takes videos of up to 4 GB and 10 hours. Pro を見る
Add subtitles to video について
Add subtitles to video joins a subtitle file you already have — from a translator, a download, YouTube Studio or our Subtitle generator — to the video it belongs to. It reads SRT and WebVTT, strips their formatting tags, and works out the text encoding: UTF-8 files and UTF-16 files with a byte-order mark are read directly, and older Windows code pages such as Cyrillic Windows-1251 can be picked by hand when letters come out wrong. Arabic, Persian and Hebrew lines are drawn right to left.
There are two ways to add them. Burning in paints every line onto the frames, exactly as the preview shows it, and re-encodes the video as H.264 MP4 (or VP9 WebM for WebM and MKV sources); the captions then show on any phone, social network or messenger, but nobody can switch them off. A separate track keeps the picture and sound as they are and adds a text stream: mov_text in MP4 and MOV, SRT in MKV, WebVTT in WebM, with other inputs saved as MKV. It takes seconds and can be marked with a language and shown by default, but it only appears in players that read subtitle tracks, such as VLC, QuickTime, phone video players and smart TVs; Instagram and TikTok ignore it.
Only the first video and audio track are kept. The tool doesn't edit, translate or write subtitles; for timing or text changes, use the Subtitle generator's editor first.
プライバシー
The video and the subtitle file are read and processed only in this browser tab. Burning in uses mediabunny with your browser's WebCodecs encoder, or ffmpeg.wasm in a Web Worker; adding a track uses ffmpeg.wasm. Nothing is uploaded, and the 31 MB ffmpeg engine fetched from jsDelivr when needed contains none of your data.
主な機能
Burn in, styled
Font, size, colour, box, outline or shadow and position, drawn exactly as previewed.
Switchable track
mov_text in MP4, SRT in MKV, WebVTT in WebM, with a language tag and default flag.
Any language
UTF-8 and legacy code pages, with right-to-left drawing for Arabic and Hebrew.
Fix the offset
Shift every line earlier or later in half-second steps.