Add Subtitles to Video

Add subtitles to a video for free — open or paste an SRT or VTT subtitle file and burn the captions permanently into your MP4, with a choice of size, font, colour, dark box, outline or shadow, and top or bottom position. Perfect for social media, where most videos play muted. Runs privately in your browser.

100% private — your video is processed on your device, never uploaded. Conversion happens on your device; nothing is uploaded.

Drop a video (or an .srt file)Click to browse or drag it here

Processing uses your browser’s built-in video encoders (WebCodecs) through the open-source Mediabunny library — your files are never uploaded. Works best in recent Chrome, Edge and Safari.

How to add subtitles to a video

Drop your video in the box.
Paste the SRT or VTT subtitles, or open the subtitle file.
Choose text size, style, colour and position.
Click Burn subtitles into video, preview and download the MP4.

What you can use it for

Caption videos for Instagram, TikTok and LinkedIn, where most people watch muted
Make accessible videos with always-on captions
Add translated subtitles for international audiences
Create captioned clips from interviews and talks

More free tools

Designing with text?

Style, caption and decorate text with our free, private text and image tools.

Fancy Text Bold Text Add Text to Image Meme Generator Text Shadow Bubble Text Glitch Text Watermark Image

See all free tools →

Frequently asked questions

How do I add an SRT file to a video permanently?

Drop the video in, open the .srt file, pick a style and click Burn subtitles into video. The captions become part of the picture, so they show on every player and platform.

I don't have a subtitle file — can I make one?

Yes — our Subtitle Generator creates an SRT automatically from the speech in your video. Download it, then open it here.

Burned-in or separate subtitles?

Burned-in captions always show and can't be turned off — best for social media. Separate SRT/VTT files can be switched on and off, and are better for YouTube and accessibility settings.

Is my video uploaded?

No. The video is read and encoded by your own browser using its built-in video encoders, so it never leaves your device — even large or private videos stay private.

Is there a file size limit?

There's no upload limit. The finished video is held in memory before download, so files up to a few GB work on most computers; very large files need more RAM.

Which browsers work?

Recent Chrome, Edge and Safari work best (they have hardware video encoders). Firefox 130+ works for most files.