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SRT ↔ VTT Subtitle Converter

Parse, validate, and convert SubRip and WebVTT subtitles locally, flagging malformed timestamps, overlaps, gaps, and empty cues instead of ignoring them.

LocalNo subtitle retention

Reviewed July 17, 2026

Guide, examples, and validation Show

About this tool

Convert between SubRip and WebVTT subtitle files without uploading them, and see exactly which cues have timing or structural problems.

  • Parses SubRip index and timing blocks and WebVTT signature, NOTE, STYLE, and REGION blocks, requiring comma-separated HH:MM:SS,mmm timestamps for SubRip and dot-separated HH:MM:SS.mmm (or MM:SS.mmm) timestamps for WebVTT.
  • Reports per-cue issues as explicit notes: malformed or out-of-bounds timestamps stop with a named error, while overlapping cues, out-of-order cues, index gaps, empty cues, and zero durations are surfaced as warnings.
  • Strips WebVTT-only styling and inline tags when producing SubRip, renumbers cues sequentially starting at 1 (reporting a note when numeric WebVTT cue identifiers change), removes a leading byte-order mark, and exports a versioned JSON evidence report of every converted cue.

How to use Subtitle Converter

Choose the conversion direction, paste SubRip or WebVTT text, convert it, then review the cue count and validation notes before downloading the converted file or the JSON evidence report.

When this tool is useful

  • Converting a caption file between SubRip and WebVTT for a player or platform that requires one format.
  • Checking a subtitle file for malformed timestamps, overlaps, gaps, or empty cues before shipping it.

Practical tips

  • Read every note: overlapping, out-of-order, and empty cues convert but often indicate an authoring mistake.
  • Remember that WebVTT positioning, STYLE, REGION, and inline tags are dropped when producing SubRip because the format has no equivalent.

Examples you can test

Load an example, compare the result with the expected output, then replace it with your own input.

Convert SRT to WebVTT

Example input

A two-cue SubRip file with comma-decimal timestamps

Expected output

A WEBVTT file with period-decimal timestamps plus any per-cue notes

A successful conversion validates structure and timing, not how a specific player renders the cues.

Validation checklist

  • Confirm the selected direction matches the pasted format.
  • Resolve or accept every overlap, gap, and empty-cue note.
  • Open the downloaded file in the destination player before replacing the original.

Frequently asked questions

Which subtitle formats are supported?

SubRip (.srt) and WebVTT (.vtt) plain text, in both directions. Other formats such as ASS/SSA, TTML, or SBV are outside the supported set and are not parsed.

What happens to WebVTT styling and positioning?

WEBVTT STYLE and REGION blocks, per-cue settings such as line and position, and inline tags such as voice or class are dropped when converting to SubRip, and each drop is reported as an explicit note.

How are timing problems handled?

Timestamp separators are enforced per format: SubRip must use commas (HH:MM:SS,mmm) and WebVTT must use dots (HH:MM:SS.mmm), so a dot-separated SubRip timestamp or a comma-separated WebVTT timestamp stops the conversion with a named error. A missing timing line or an end time before its start also stops with a named error. Overlapping, out-of-order, empty, or zero-length cues are converted but reported as notes so nothing is silently changed.

Are my subtitle files uploaded anywhere?

No. Parsing, validation, conversion, copying, and downloads all run in your browser. No subtitle text is sent to a server, and nothing is retained after you leave the page.

What are the limits and what is not verified?

Up to 2,000,000 characters, 20,000 cues, 20,000 characters per cue and per line, and timestamps under 100 hours. The converter validates structure and timing, not translation quality, encoding beyond BOM removal, or how a specific player renders the result.

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