Is my video uploaded to a server?

No. The video is read locally by your browser using the File API. Nothing is sent to any server — your files never leave your device.

What subtitle formats are supported?

The tool accepts SRT (.srt) and WebVTT (.vtt) text. SRT is automatically converted to WebVTT before attaching to the player. Paste the text directly or upload the file.

Can I hard-encode subtitles into the video file?

No — hard-encoding requires FFmpeg running server-side. This tool produces a preview overlay and a downloadable VTT file. Use the FFmpeg command "ffmpeg -i input.mp4 -vf subtitles=subs.srt output.mp4" to burn them in.

Why are my subtitles not showing in the player?

Make sure your video format is supported by the browser (MP4/H.264 or WebM work in all modern browsers). Also check that the SRT timestamps use the HH:MM:SS,mmm --> HH:MM:SS,mmm format with a comma before milliseconds.

What is the difference between SRT and VTT?

SRT (SubRip) uses a sequential cue number + timestamp format with commas for milliseconds. WebVTT is the browser-native format — it uses dots for milliseconds and starts with "WEBVTT". Both carry the same timing and text data.

Can I edit subtitle cues in this tool?

Yes. After parsing, each cue appears in an editable list below the player. Edit the text directly and click "Re-apply" to update the subtitle track without reloading the video.

Add Subtitles To Video

Load a video and an SRT or VTT subtitle file, preview subtitles live in the browser, and download the converted WebVTT file.

Video File

Drop a video or browse MP4, WebM, MOV, OGG…

Subtitle File (SRT or VTT)

Upload file

Load a video and subtitle text, then click Preview

Summary

Load a video and an SRT or VTT subtitle file, preview subtitles live in the browser, and download the converted WebVTT file.

How it works

Choose a video file (MP4, WebM, MOV, or any browser-supported format).
Paste SRT or VTT subtitle text into the text area, or upload an .srt / .vtt file.
Click "Preview" to attach the subtitles to the video player as a native WebVTT track.
Play the video — subtitles appear as a styled overlay synchronized to the video.
Edit individual cues in the parsed cue list and re-apply to update the track.
Click "Download VTT" to save the converted WebVTT file to your device.

Use cases

Preview how SRT subtitles look before hard-burning them with FFmpeg.
Convert SRT files to WebVTT for use with HTML5 video players.
Quickly check subtitle timing and synchronization against a video file.
Edit individual subtitle cues and re-download the corrected VTT file.
Verify auto-generated captions from speech-to-text tools before publishing.
Test subtitle display on different video aspect ratios without encoding.

Frequently Asked Questions

Last updated: 2026-09-22 · Reviewed by Nham Vu