| Zotero | Mendeley | Online Generator |
| Use Permission | Open Source | Free | Free (Depends on the generator) |
| Access | Web-based, desktop application and mobile app. | Web-based, desktop application and mobile app. | Web-Based |
| How to save the reference? | Browser Connecter support Chrome/Firefox/Mircosoft Edge/Safari | Web Importer support Chrome/Firefox/Mircosoft Edge | One-Off Generator |
| Can I save references from external databases? | Limited: ISBN,DOI,PMID | No | N/A |
| Support Type of Word Processor | MS Word, LibreOffice, Google Doc | MS Word, Libre Office, | N/A |
| Name of Plugin | N/A (Auto Install) | Mendeley Cite | N/A |
| Can I upload the attachments? | Yes, with the option to annotate automatically; annotate and highlight | Yes, also can annotate and highlight | N/A |
| Duplicate detection | Yes | Yes | N/A |
| Captures webpage snapshots? | Yes | Yes | N/A |
| Citation / bibliography styles | List of citation styles in Zotero | List of citation styles in Mendeley | Updated at the discretion of the website |
| Export | BibTex, RIS, Refer/BiblX, Bibliontology, MODS | BibTex, EndNote (XML), RIS | Copy & Paste from the browser |
| Sharing/Collobration | Yes | Yes: small groups up to 3 are free. Costs for larger groups | N/A |
| Extra Cost | Free with 300 MB of storage. Additional storage and group upgrades are available for a fee. | Free with 2GB Web storage, 500 MB each for personal shared storage. Additional storage and group upgrades are available for a fee. | N/A (Depends on the generator) |
| Other Features | Will automatically attach PDFs. | Can search the Mendeley database (papers in the libraries of other users) | No installation is required |
