Best Research and Citation Extensions

How we separated the picks

Citation generation, reference management, paper explanation, annotation, and highlighting are different jobs. The best stack may use more than one tool, but each additional extension adds permissions and workflow overhead.

Best overall research capture

Zotero Connector

Structured references, PDFs, and snapshots flow into a durable library.

4.0 / 57,000,000 usersFree and open source; optional paid Zotero storage

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Best quick citations

MyBib

Fast, free citation output for shorter projects.

4.8 / 51,000,000 usersFree; publisher says no ads

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Best paper explainer

SciSpace

Designed to make academic language and methods easier to navigate.

4.4 / 5200,000 usersLimited free use; paid plans

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Best highlighting workflow

Glasp

Collects notes across web pages, PDFs, and video transcripts.

4.5 / 5500,000 usersFree tier; paid plan options

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Best collaborative annotation

Hypothesis

Open annotation on pages and PDFs, widely used by courses and research groups.

4.1 / 5200,000 usersFree for individual use; paid education tiers exist

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Best quick paper lookup

Google Scholar Button

One click from any page to Scholar results, citations, and full text.

4.6 / 53,000,000 usersFree

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Best classroom PDF annotation

Kami

Markup, comments, and classroom sharing on PDFs — the schoolwork-first annotation pick.

4.6 / 54,000,000 usersFree tier; paid plans for schools and power features

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If your notes live in Notion

Notion Web Clipper

Convenient only inside a Notion workflow: its 3.3 store rating reflects recurring clipping-fidelity complaints, and it produces no citation metadata.

3.3 / 51,000,000 usersFree with a Notion account

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What to check before installing

1. Verify every citation against the original source.
2. Keep a durable copy of sources, not only AI summaries.
3. Use primary sources whenever the claim allows it.

Sources

Rankings use current store records, feature coverage, and first-party developer documentation.

1. Chrome Web Store listing

   Store facts, source-capture features, and privacy statement.

2. Chrome Web Store listing

   Store facts, citation claims, and bandwidth disclosure.

3. Chrome Web Store listing

   Store facts, product scope, and disclosed data handling.

4. Chrome Web Store listing

   Store metrics and supported formats.

5. Chrome Web Store listing

   Store facts and data categories.

6. Chrome Web Store listing

   Store facts and data categories.

7. Chrome Web Store listing

   Store facts and privacy disclosure.

8. Chrome Web Store listing

   Store facts, rating history, and data categories.