Subtitle Time Shifter
Local-first
Shift SRT or VTT subtitle timestamps forward or backward by milliseconds.
What is Subtitle Time Shifter?
Shift SRT or VTT subtitle timestamps forward or backward by milliseconds.
How to use it
- Paste the SRT, VTT, timestamps content you want to process.
- Adjust quality, size, or output options when available.
- Run the tool to shift subtitle timestamps and preview the result on the page.
- Copy the output or download the generated file when it looks right.
Best use cases
- Clean developer data during debugging, API work, and documentation.
- Clean content before saving configs, sharing snippets, or importing tables.
- Use it when privacy matters and the input should stay inside the browser.
Official standards and scope
Matroska and YouTube provide the SRT/VTT caption context; this page shifts text that looks like a timestamp in a pasted caption file. It reads either a first line such as shift=1500 or a signed integer on the first line, requires a non-zero integer shift in milliseconds, then replaces every matching HH:MM:SS or H:MM:SS timestamp with one to three fractional digits. Minutes and seconds above 59 are rejected, fractional digits are padded or truncated to milliseconds, the original comma or dot separator is retained, and negative results are clamped to 00:00:00,000. The rest of the text is not parsed into cues, and the tool does not validate SRT/VTT headers, cue numbering, cue end-after-start, ordering, overlap, encoding, or line lengths. The first shift instruction line is removed and the output is trimmed with one final LF.
- Matroska Technical Documentation: SRT subtitles - Matroska project
- YouTube Help: Supported subtitle and closed caption files - YouTube
Sources checked July 27, 2026. Standards, dependencies, and platform rules can change; review the original sources again before formal integration or publication.
Notes
- Browser support for SRT, VTT, timestamps can affect preview and export behavior.
- Invalid input will show an error when possible, but the tool will not guess missing fields.
- Preview the result before using it in production, publishing, or submission workflows.
FAQ
Which formats are supported?
SRT comma timestamps and VTT dot timestamps are both supported.
Is Subtitle Time Shifter free to use?
Yes. You can use it directly in the browser without creating an account.
Does Subtitle Time Shifter support batch processing?
Text tools usually process one pasted input at a time, so split large jobs into smaller inputs.
Are files or content uploaded?
Subtitle Time Shifter runs in your browser, so your input or files are not uploaded to DataHub servers.
Can I use Subtitle Time Shifter on mobile?
Yes, but desktop browsers are better for large files, batch conversion, or long text input.
Why can conversion or validation fail?
Common causes include invalid syntax, missing required fields, or invisible characters copied with the input.
Can I use the result commercially?
The tool only processes your own input. Commercial use depends on the rights of the original file or data.