Podcast Chapters Editor
Add chapters to your local episode and convert chapter formats without uploading audio.
Try before you buy.
- Free preview: your original audio and editable markers, plus the first rows of the generated chapter file; complete chapter exports stay locked.
- Locked until you unlock it: download and copy.
- Unlock: Pro pass, ₹179 for 30 days or ₹79 for 1 week, a one-time payment that never renews. Unlock: Pro pass, $5.99 for 30 days or $2.99 for 1 week, a one-time payment that never renews.
Ways to unlock shows how to get the full result.
Printing this result is locked in the free preview.
The player and the waveform appear here with your audio. Without audio you can still type positions or import chapters.
Audio stays local. Use the player or click the waveform; the labelled position input is the keyboard alternative.
Import and edit
Chapter file preview
Complete exports need a Pro pass. JSON permits untitled silent markers. YouTube requires a zero start, three visible titled chapters and at least ten seconds per chapter. Original audio bytes remain unchanged.
Locked in the free preview. Opens the ways to unlock this result.
Locked in the free preview. Batch runs unlock with a pass.
Locked in the free preview. Query results unlock with a pass.
About the Podcast Chapters Editor
Play your local podcast with a waveform, drop markers at the playhead, and give each marker an optional title, image or link. Import existing MP3 CHAP/CTOC frames, a Podcasting 2.0 JSON file, a CUE sheet or pasted timestamp list. With a Pro pass, export a copied MP3 with chapter and table-of-contents frames, Podcasting 2.0 chapters JSON, WebVTT or checked YouTube description timestamps. Non-MP3 audio keeps JSON and VTT output. Your original recording is never uploaded or overwritten. The free preview keeps your original audio and marker editor available and shows the first rows of generated JSON; a Pro pass opens the complete exports.
How to use it
- Choose your local episode to calculate its waveform and duration, or import a chapter file or pasted timestamp list.
- Play or seek the original audio, then Add marker at this position. Edit start/end times, title, image reference, link and navigation visibility.
- Optionally embed your own PNG/JPEG chapter artwork for the MP3. Links and image references are stored as metadata and are not opened by this page.
- Choose MP3, JSON or WebVTT output. The last end is inferred from the episode duration where needed; MP3 export requires an MP3 original.
- For YouTube timestamps, start at zero, include at least three visible titled chapters and keep every chapter at least ten seconds. With a Pro pass, download or copy the checked result.
MP3 chapter frames
The writer follows the ID3 Chapter Frame Addendum: chapter positions are milliseconds and VBR byte offsets are left at the specified all-ones sentinel. Unrelated metadata frame payloads and audio bytes are carried over. An absent root table of contents declares no navigation table; CHAP-only markers are retained as silent markers until you select visible chapters.
JSON and platform timestamps
Podcasting 2.0 chapters JSON requires a string version and a chapters array; only each chapter’s numeric startTime is required. Untitled silent markers and optional endTime are supported. YouTube chapter rules apply only to the YouTube timestamp export, never to JSON, MP3 or VTT.
Limitations
- A podcast player decides whether it reads embedded MP3 chapters. The page checks the file’s chapter bytes but cannot guarantee every player’s behavior.
- ID3v2.3 and v2.4 are supported. Mixed-version stacked tags, encrypted/compressed chapter frames and malformed tags are refused before a new file is saved; optional extended headers, CRC and footers are normalized.
- CUE times are minutes:seconds:frames at 75 frames per second. INDEX 00 is pregap; INDEX 01 is the chapter start. Multi-FILE sheets require a matching episode rather than flattening file-relative times.
- A waveform needs a decoder supported by this browser. Large MP3 tag edits still require memory for the original and copied file.
- Embedded image references may be followed by an external podcast player after export. This page never fetches them.
- MySmartCoPilot is not affiliated with or endorsed by YouTube.
Privacy
On this device; its files download once
Original audio, waveform samples, chapter text and artwork stay on this device. Image and link references are not fetched, checked or uploaded.
Frequently asked questions
What do I get without a pass?
Without a pass, Podcast Chapters Editor shows your original audio and editable markers, plus the first rows of the generated chapter file; complete chapter exports stay locked. Until you unlock it, the result can’t be downloaded or copied. A Pro, Premium or Ultimate pass, a one-time payment that never renews, unlocks the full result. The pricing page lists the passes and their prices.
Does adding chapters re-encode my MP3?
No. The audio data is copied byte for byte. The page writes and reads back the chapter metadata and compares the copied audio before saving.
Can JSON have one chapter or a silent marker without a title?
Yes. The format only requires startTime for a chapter. YouTube’s first-zero, three-chapter and ten-second checks apply only when exporting its description timestamps.
Why does an imported MP3 show silent markers?
CHAP frames without a root CTOC do not declare a navigation table. The editor keeps those markers without inventing navigation; select visible markers to add an ordered table of contents.
What is shown without a pass?
Your original audio and editable markers remain available, with the first rows of the generated file. Complete MP3, JSON, VTT, timestamp and copy exports need a Pro pass.
Open-source components
This page can load these open-source components, each only when a task needs it:
- It uses FFmpeg under the LGPLv2.1, through the Mediabunny add-ons: licence and source code.
- It uses Mediabunny under the MPL 2.0: licence and source code.
You may replace them with your own builds. Their licences and the credits of every library the site uses are on the open-source credits page.