Merge duplicate Zotero references while keeping their organization

Zotero provides Duplicate Items and Merge Items for consolidating records that describe the same work. Merging retains collection and tag information, as well as citation links associated with the records. That makes it the appropriate action when you want one reference without losing its organization. A proposed duplicate still needs your review: Zotero’s matching can produce false positives. Zotero: Duplicate Detection

Merge the two records

1. Find the proposed pair in Duplicate Items. Start with the two records you intend to consolidate. Zotero uses the title, DOI, ISBN, and sometimes the year or creator to detect duplicates. Treat the match as a prompt to compare the records, not as a decision that they are identical. Duplicate matching works only within one library. Zotero: Duplicate Detection

2. Confirm that both records describe the same work. Compare the full title, authors, DOI or ISBN where present, year, and any other fields that distinguish the work. A similar title alone is insufficient. If a field conflicts, resolve what it means before proceeding. For example, check whether the records describe different works or whether one record simply has incomplete or incorrect information. If you cannot establish that they are the same work, leave them separate.

3. Review the information you want to keep. Selecting an item in Duplicate Items makes Zotero co-select the proposed match. In the right pane, choose the master item from the list at the top and, for fields that disagree, use the controls beside each field to keep a better value from another record. Compare each choice with the actual source before merging. Zotero: Duplicate Detection

4. Use Merge Items for the confirmed pair. Click Merge 2 Items (or the displayed number) in the right pane after the identity check and field choices. Deleting one record may discard organization or disrupt citation links; Zotero recommends merging to retain that information. Zotero: Duplicate Detection

5. Review the consolidated record. Read its title, author, identifier, and other fields you compared. Check that the collection and tag information you expected to retain is represented. If a value looks wrong, address that specific field rather than assuming the duplicate match chose the best version automatically.

Before you move on

Use this short check to decide whether the task is complete:

• The two original records were for the same work, including any conflicting title, creator, year, or identifier details.
• The consolidated record shows the master values you intended to keep.
• Its collection and tag information reflects the organization you needed to preserve.
• You used a merge for the confirmed duplicate rather than deleting one of the records. Zotero: Duplicate Detection

If the records are in different libraries, Duplicate Items will not match them across that boundary. If they appear together but you cannot resolve a meaningful difference, do not merge on the strength of the suggestion alone. Those are limits of this workflow, not reasons to guess at a master value. Zotero: Duplicate Detection

When two records describe different works that are meaningfully connected, retain both and use Zotero Related Items to link them. A review and its reviewed work are an example: a merge would collapse two citeable sources into one record. Reserve Merge Items for copies of the same work, and verify the pair before committing.

Documentation check: Zotero Documentation 1, Zotero Documentation 2, reviewed September 29, 2026. The menu paths and feature limits come from these pages; the result checks are steps for the reader. This workflow was not run in a live product profile. Check the current interface and your saved result before relying on either.