ONE FOCUSED REPAIR DESK

Small corrections. Easier captions.

CaptionClean is a free browser tool for the last practical fixes between an existing subtitle file and a video you are ready to share.

Why this tool exists

A caption file can have useful words and still need attention: numbering has gaps, pasted text contains extra spaces, every cue is a little late, or the player needs WebVTT instead of SRT. CaptionClean puts those common repairs in one simple workflow with a readable output you can inspect.

What it does

The tool reads SRT and WebVTT, checks cue timestamps and text, applies a constant timing offset, regenerates cue numbers, optionally cleans horizontal whitespace and markup, and exports either format. It explains when a negative offset clips or removes opening cues and when WebVTT information is left out.

What to use another editor for

CaptionClean does not transcribe audio, translate captions, detect speakers, or correct timing drift. It does not preserve WebVTT positioning settings, notes, regions, styles, or identifiers. For detailed placement, time stretching, translation review, or accessibility editing, use a dedicated subtitle editor and preview the result with your video.

Built around browser-local processing

You can use the tool without an account. Subtitle content stays in your browser, and there is no subscription or conversion fee. It currently runs without advertising or analytics scripts. Read the privacy page for how page delivery and contact messages are handled.

Operator and feedback

CaptionClean is maintained by the independent FMFM Stars project. For questions or a reproducible bug report, email fmfm.stars@gmail.com. A small invented subtitle example helps us understand a problem without collecting private files.

Start with the practical subtitle guide if you are unsure which offset or output format to choose.