Convert SRT to VTT and VTT to SRT subtitles

How it works

The conversion has three deterministic stages, all running in this tab:

1. Detect. The input format is detected from the content (a WEBVTT header means WebVTT; numbered or timestamp-led cues mean SRT), or taken from your chosen direction.
2. Parse. Cues are read into a neutral list of start time, end time, text triples at millisecond precision. WebVTT comment (NOTE) and style (STYLE) blocks are skipped, and cue settings such as position or alignment are ignored because SRT has no equivalent.
3. Serialize. The cues are written in the target format: numbered cues with comma milliseconds for SRT, a WEBVTT header with dot milliseconds for VTT. Cue text — including inline tags like <i> — is preserved verbatim.

Downloads are generated with the browser's Blob API and never touch the network. The same input always produces the same output, so re-running a conversion is safe and diffable.

When would you convert SRT to VTT?

The conversion itself is mechanical — timings and text stay the same and only the notation changes. People convert subtitles for a few common reasons:

• Uploading captions to YouTube. YouTube accepts both .srt and .vtt caption files, so converting between them is a routine step when you receive subtitles in one format and need the other.
• Adding subtitles to a web page. HTML5 <video> uses <track> with WebVTT (.vtt) files, so an SRT file converted to VTT can be used directly on the web with no extra tooling.
• Working with learning platforms. Moodle, Canvas, Kaltura, and Panopto accept WebVTT; converting your SRT export keeps the same cues without re-typing anything.
• Sharing with tools that expect one format. Many caption editors and players export only SRT or only VTT. Because this converter runs locally, the file never leaves your device while you switch formats.

SRT vs WebVTT: what changes when you convert?

SRT (SubRip) and WebVTT both store cues as start/end timestamps plus text, but they use different notation. Here is exactly what changes — and what stays the same:

The same cue in both formats — only the header, the cue number, and the comma/dot separator differ; timing and text are identical:

1
00:00:01,000 --> 00:00:04,000
Hello from the first cue

WEBVTT

00:00:01.000 --> 00:00:04.000
Hello from the first cue

Supported inputs and limits

• Formats: SRT (with or without cue numbers) and WebVTT, in either direction. Both comma and dot millisecond separators are accepted on input.
• Preserved: cue timing to the millisecond and cue text verbatim, including multiline cues and inline tags.
• Dropped on conversion: WebVTT cue settings (position, align, line) and WebVTT NOTE/STYLE blocks — SRT cannot represent them.
• Size: bounded by this browser tab's memory. Very large subtitle files may take a moment.
• Limits: this prototype converts SRT and WebVTT only. It does not translate, re-time, or merge subtitles, and it never embeds subtitles into video files.

Frequently asked questions

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