Find duplicate books

Clean up repeated copies without letting the app delete anything automatically.

Why duplicates happen

Large libraries accumulate repeated books over time: the same title in two locations, an older copy and a newer edition, a file already in your archive and another copy waiting in the Inbox.

Papyrium helps surface those cases so you can decide what to keep, merge, delete, or ignore. It does not automatically remove books.

How Papyrium finds duplicates

Duplicate groups can be found in a few ways:

  • Same ISBN. Useful for likely matches across different files or formats.
  • Identical file. Useful when the same file has been added more than once.
  • Same title and author. Useful for possible matches that need human review.

Some matches are stronger than others. Papyrium labels likely duplicates so you know when to review carefully instead of treating the group as an obvious duplicate.

When duplicates are checked

Papyrium checks for duplicates after import and can also scan the library manually. If new duplicate groups are found after an import, a banner appears so you can open the review flow.

This pairs especially well with the Inbox: put new additions there first, then check whether they already exist elsewhere in the library before you organize them.

What you can do with a duplicate group

Merge

Keep one book as the primary entry and move the other files into it. This is useful when the duplicates represent the same book record and you want one clean entry.

Trash

Send a redundant copy to your system Trash — recoverable until you empty it. For locations where Trash is not available (such as a NAS), Papyrium shows a confirmation dialog before permanently deleting.

Dismiss

Hide a group when it is not actually a problem. For example, you may intentionally keep different editions or translations as separate books.

Review before changing anything

Duplicate cleanup is intentionally review-based. Matching by ISBN or identical file is often strong, but title-and-author matches can include false positives: different editions, revised releases, translations, companion volumes, or books with similar metadata.

Papyrium gives you the group and the available details; you choose the action.

Good cleanup workflow

  1. Add new items to the Inbox or import them into the library.
  2. Open the duplicate review when Papyrium finds matches.
  3. Merge obvious duplicates that should be one book entry.
  4. Delete extra copies only when you are sure you do not need them.
  5. Dismiss groups that are intentional separate books.

Use duplicates with MCP

The local MCP server can expose duplicate groups to an AI agent, so the agent can help triage a messy Inbox or explain why books were grouped — and, when Allow deletions is enabled, resolve them: merge a group into a single entry (keeping every file and annotation) or send a redundant copy to your system Trash. The agent sees exactly which fields differ between copies first, and every change previews before it is applied. You can also keep using Papyrium's own review flow.

Related

For staging new additions before cleanup, see Folders & Imports. For agent-assisted cleanup, see AI Agents & MCP.