Managing Duplicates in Your Zotero Library

Sometimes, while doing lots of research over time, you can accidentally save the same source twice to your Zotero library. This can cause problems when using the Zotero Word or Google Docs plugin to create a bibliography - you may end up with the same article twice appearing in your bibliography as well. 

(Note: You can copy a Zotero record into as many folders or subfolders in your Zotero library as you like. These are not considered duplicates, and will not cause trouble with your bibliography.) 

Luckily, Zotero has a tool to help you manage these duplicates. There is an automatically generated folder titled "Duplicate Items" that appears in the left-hand menu of the Zotero program. When you have no duplicates, this folder is empty. In the example screenshot below, you see Zotero has identified 3 articles that each appear twice in my library. 

 

Merging the duplicates into a single record will avoid future problems while citing, and keep your library looking less cluttered. Click on one of the identified records, and you'll see an option to choose a master copy of the two or more duplicate records. 

 

Once you have selected your preferred master copy, click 'Merge 2 items.' (If you have 3 or more items to merge, this button may change its name accordingly.)

 

Repeat this step with any other duplicates Zotero identified.