Subtitle Converter

Convert subtitles between SRT, WebVTT, SMI (SAMI) and plain text, with optional time shifting.

Category: Converters

When to use?

Use it when a subtitle file’s format doesn’t match your player, or when subtitles are out of sync. Convert between SRT, WebVTT, SMI and text, and shift every cue earlier or later by a chosen number of seconds.

How to use

  • Choose the source format (auto-detect available) and target format.
  • Paste the subtitle content.
  • Optionally enter a time shift (seconds), then copy or download the result.

Input Explanation

Paste subtitle text. With "auto-detect" on, the format is recognized automatically. Time shift is in seconds (negative allowed).

Calculation Basis

Subtitles are parsed into cues (start/end time + text) and re-serialized into the chosen format. Time shifting adds an offset (ms) to every cue.

Usage Examples

  • Player compatibility - Convert between SMI/SRT/VTT for your player.
  • Sync correction - Shift all cues at once to match the video.

Examples

  • SMI → SRT for mobile player compatibility
  • Time shift −1.5s to move subtitles 1.5 seconds earlier

Cautions

  • Complex SMI styling (multiple language classes, positioning) may be simplified during conversion.
  • Plain text input has no timing, so each paragraph becomes a 3-second cue as a starting point.

FAQ

Which formats are supported?

SRT, WebVTT, SMI (SAMI) and plain text, in any direction.

Can I fix subtitle sync?

Yes — enter a time shift (seconds) to adjust every cue.

Is my file uploaded?

No. All conversion happens only in your browser.

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