VTT to SRT Converter
Professional WebVTT to SubRip converter with batch processing, time-shifting synchronization, and HTML tag stripping. Client-side privacy focused.
About
This utility transforms WebVTT (Web Video Text Tracks) files into the widely supported SRT (SubRip Subtitle) format. While VTT is the standard for HTML5 web players, legacy media players and editing software (like Premiere Pro or DaVinci Resolve) often require SRT. This tool parses the cue payload, strips VTT-specific metadata (such as positioning coordinates and styling tags), and reformats timestamps from MM:SS.ms to the strict HH:MM:SS,ms standard.
The converter runs entirely in your browser using the FileReader API. No file data is sent to a server, ensuring 100% privacy for pre-release scripts. It includes an advanced Time Shift algorithm to correct desynchronization by applying a global millisecond offset to every cue block.
Formulas
The core conversion logic involves normalizing timestamp syntax and calculating time offsets. The timestamp transformation follows this pattern:
Where t is time and k is the user-defined offset in milliseconds. The parsing engine uses the following RegEx to extract and normalize time components:
Reference Data
| Feature | WebVTT (.vtt) | SubRip (.srt) |
|---|---|---|
| Header | WEBVTT (Required) | None (Forbidden) |
| Timestamp Format | 00:00:05.500 (Dot separator) | 00:00:05,500 (Comma separator) |
| Cue Structure | ID (Optional) + Timestamps + Settings | Index (Required) + Timestamps |
| Styling | Rich CSS (align:start, <c.v>) | Basic HTML (<b>, <i>) |
| Comments | NOTE blocks supported | Not supported |
| Decimal Precision | 3 digits (milliseconds) | 3 digits (milliseconds) |