Migrate manga between sources
Sources come and go. A site shuts down, an extension breaks, or another source has better scans. Migration moves a series in your library from one source to another without losing your place: the new entry takes over, and your reading progress, categories, and tracking come along.
Start a migration
Open the series you want to move:
- Phone: tap the ⋮ menu in the top bar and choose Migrate.
- Tablet / desktop: tap the swap-arrows Migrate button in the top bar.
Find the series on another source
Tsumiru opens Search All Sources and immediately searches every source for the series' title. Each source shows its matches as a row of covers; entries already in your library appear darkened.
If the right match doesn't show up, edit the search yourself — sources often index under slightly different names, so try the romanized title (Boku no Hero Academia instead of My Hero Academia).
Tap the cover of the series on its new source.
Review the preview
The Migration Preview shows the old and new entries side by side — check the title, source, and chapter details before going further.
Under Migration Options you choose what carries over:
- Migrate Chapters — copies your read status (plus last-read page and bookmarks) to the matching chapters on the new source.
- Migrate Categories — puts the new entry in the same categories as the old one.
- Migrate Tracking — points your tracker links (AniList, MyAnimeList, …) at the new entry.
- Delete Source Manga — removes the original entry from your library once migration finishes.
By default chapters, categories, and delete are on and tracking is off. The Quick preset is the safe pick: chapters and categories on, and the original kept in your library so you can verify the new entry before removing the old one yourself. Custom just means you've changed the switches.
Tap Start Migration and confirm the from/to titles; the migration runs with a progress screen, and when it finishes you get a summary of what moved, with warnings for anything that couldn't.
No undo
Migration can't be reversed. If Delete Source Manga is on, the original leaves your library when it completes — double-check you picked the right target first.
What carries over, exactly
- Reading progress: chapters are matched between the two sources by chapter number first, then by chapter name. When the two sources number their chapters differently, some read statuses may not find a match — the summary tells you if that happens. Nothing is marked unread; matches are only ever marked read.
- Categories: the new entry is added to the old entry's categories. Nothing is removed from the old one.
- Tracking: each tracker bound to the old entry is bound to the new one.
- Server downloads do not move. Chapters your server downloaded came from the old source; queue fresh downloads on the new entry if you want them.
- Delete Source Manga removes the old series from your library — it doesn't scrub anything else from your server.