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Validate and Format a Complete Video Chapter List

Normalize chapter timestamps while preserving row-level sequence errors.

Drop or choose a file up to 2 MB. Its contents replace the main text input; the filename alone is never treated as data.

Reviewable output

Processed

Warnings / conflicts

Output state

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How the calculation works

Local inputboundedPer-item ruledeterministicArtifactcopy / download

How to Use This Tool

Normalize chapter timestamps while preserving row-level sequence errors. Format timestamp-and-title rows into a clean video chapter list, checking the zero start, ascending order, duplicate times and missing titles.

The work this page finishes

One nonascending or malformed timestamp can invalidate an otherwise complete chapter draft, and the error is difficult to spot in a long description. A visible row-by-row result preserves provenance, making a single correction possible without rerunning unrelated records or uploading the batch.

Rows or choicesValidate every itemReview and export
The fixture produces three normalized ascending chapters beginning at 0:00.

Deterministic workflow

Parse mm:ss or hh:mm:ss, require the first valid row to start at zero, require strictly increasing times and preserve titles after the separator. Input guards stop after 5,000 records or 2 MB, and the report separates fatal input problems from recoverable row warnings.

Why a dedicated interface helps

Paste only after every row is valid; the output deliberately retains error rows until they are corrected. Deterministic ordering, one-click copying and a downloadable artifact make repeated operational review easier than manually reconstructing a response from prose.

Assumptions

  • One chapter appears per line.
  • A vertical bar separates time from title.
  • The first chapter begins at 0:00.

Do not discard the source after export: compare the destination result with it, and remember that local execution cannot secure the surrounding device or browser add-ons.

Limitations and review boundary

It does not inspect video duration, enforce a platform-specific minimum chapter length or fetch a video description. User values are never run as script, rendered as markup or fetched as network destinations; the page writes them only into text nodes.

Verification and provenance

On 2026-08-26, the rule and examples were cross-checked with YouTube Embedded Players and Player Parameters, including a known result, a rejected input and a conflict or duplicate case. The fixture produces three normalized ascending chapters beginning at 0:00.

Sources & assumptions

Tool Spec v2 · verified 2026-08-26. Platform rules and fees can change; the editable inputs remain authoritative for your account.

Official references

Model assumptions

  • One chapter appears per line.
  • A vertical bar separates time from title.
  • The first chapter begins at 0:00.
  • It does not inspect video duration, enforce a platform-specific minimum chapter length or fetch a video description.
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Frequently Asked Questions

What does Chapter List Formatter complete?
It applies the stated formatter rule to chapter list formatter inputs and produces the reviewable output shown above.
Why use a dedicated Chapter List Formatter page instead of chat?
The Chapter List Formatter workflow preserves ordering, applies identical validation on every run and creates an artifact without conversational drift.
Does Chapter List Formatter send the input to ecech?
No. Chapter List Formatter reads pasted or selected content inside the current browser tab and does not call an ecech calculation API.
What verifies the default result?
The fixture produces three normalized ascending chapters beginning at 0:00.
When should I reject the output?
It does not inspect video duration, enforce a platform-specific minimum chapter length or fetch a video description.
Which reference supports Chapter List Formatter?
The recorded Chapter List Formatter reference is YouTube Embedded Players and Player Parameters, reviewed 2026-08-26.

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