Zathura
Focus: document viewer, keyboard driven and open source. Shares pdf and reading with Hypothesis. A desktop app, not a browser extension. Adds Linux. Rated 4.4 (Hypothesis: 4.5).
Desktop AppFreeLinux
4.4Visit
Browser Extension
Hypothesis
Highlight and annotate any web page or PDF, privately or in groups.
Rating
4.5 / 5
Pricing
Free
Difficulty
Beginner
Works on
Chrome, Web
Built with love by Shushant Lakhyani. Building bestproductivityresources.com
What is Hypothesis?
Hypothesis is an open-source annotation tool that lets you highlight and comment on web pages and PDFs through a browser extension. It is free for personal use and collaboration, so you can keep private notes, share annotations in a group or join public discussions on articles.
Pros: what Hypothesis does well
- Annotate almost any page
- Private or group notes
- Free and open source
Cons: where it falls short
- Extension is built for Chromium browsers
- Education features are paid
Who Hypothesis is for
Students, researchers and reading groups who want to discuss articles and papers in context.
Who can skip it
People who rarely read or annotate online.
Hypothesis alternatives
Not sold on Hypothesis? These do a similar job, and each card says what it has in common.
MIT Deep Learning Book
Focus: deep learning, book and mit. Shares pdf with Hypothesis. A course, not a browser extension. Rated 4.7 (Hypothesis: 4.5).
CourseFreeWeb
4.7Visit
Feedly
Focus: rss reader, news and blogs. Shares reading with Hypothesis. A web app, not a browser extension. Freemium (Hypothesis: Free). Adds iOS and Android. Same 4.5 rating.
Web AppFree planWeb, iOS
4.5Visit
Fluent Reader
Focus: rss reader, news feeds and open source. Shares reading with Hypothesis. A desktop app, not a browser extension. Adds Windows, macOS and Linux. Same 4.5 rating.
Desktop AppFreeWindows, macOS
4.5Visit
Wikiwand
Focus: wikipedia, ai answers and timelines. Shares reading with Hypothesis. A web app, not a browser extension. Freemium (Hypothesis: Free). Rated 4.4 (Hypothesis: 4.5).
Web AppFree planWeb, Chrome
4.4Visit
SingleFile
Focus: web archive, save web page and offline reading. Also in Research and Reading, like Hypothesis. Adds Firefox and Safari. Rated 4.7 (Hypothesis: 4.5).
Browser ExtensionFreeChrome, Firefox
4.7Visit
Free alternatives to Hypothesis
Want to spend nothing? These free picks cover similar ground.
Unpaywall
Focus: open access, research papers and academic. Also in Research and Reading, like Hypothesis. Adds Firefox. Rated 4.6 (Hypothesis: 4.5).
Browser ExtensionFreeChrome, Firefox
4.6Visit
Glasp
Focus: highlights, annotations and read later. Also in Reading and Research, like Hypothesis. Adds Safari. Rated 4.4 (Hypothesis: 4.5).
Browser ExtensionFreeChrome, Safari
4.4Visit
arXiv
Focus: research papers, preprints and open access. Also in Research and Reading, like Hypothesis. A website, not a browser extension. Rated 4.8 (Hypothesis: 4.5).
WebsiteFreeWeb
4.8Visit
Paul's Online Notes
Focus: maths, calculus and algebra. Also in Research and Reading, like Hypothesis. A course, not a browser extension. Rated 4.8 (Hypothesis: 4.5).
CourseFreeWeb
4.8Visit
Wikipedia
Focus: encyclopedia, reference and research. Also in Research and Reading, like Hypothesis. A website, not a browser extension. Adds iOS and Android. Rated 4.8 (Hypothesis: 4.5).
WebsiteFreeWeb, iOS
4.8Visit
BBC Bitesize
Focus: revision, gcse and school. Also in Research and Reading, like Hypothesis. A website, not a browser extension. Rated 4.7 (Hypothesis: 4.5).
WebsiteFreeWeb
4.7Visit
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