Hypothesis

Free plan Open source APIExtensionWeb

What Hypothesis is

Hypothesis adds collaborative annotations to digital course materials, so learners can highlight passages, ask questions and discuss material in context. Users can create private highlights, page notes and threaded replies, and add tags to annotations. Supported material includes web pages, PDFs, EPUB files, YouTube videos, and content from VitalSource and JSTOR. Colleges and universities can connect Hypothesis to Canvas, Blackboard, Moodle, D2L Brightspace and Sakai through LTI 1.3; annotations can also sync with LMS gradebooks, including Canvas SpeedGrader. A free account is available for personal use and collaboration. The Free plan costs nothing, billed per student/yearly, and includes core annotation, private groups and self-service support. The web app works with a Chrome extension on Chrome and other Chromium browsers, or a bookmarklet in Firefox and Safari. Hypothesis also offers API access and export to JSON, plain text, CSV and HTML, with JSON import. It was founded as an open-source project in 2011.

Who it suits

Hypothesis suits learners and educators who want to discuss digital materials alongside the passages they are studying. Its institutional integrations are relevant to colleges and universities using supported learning management systems.

What it does well

Annotations support private highlights, notes, tags and threaded replies.
Supports web pages, PDFs, EPUB files and YouTube videos.
LTI 1.3 integrations include Canvas, Moodle and Sakai.
Free plan includes core annotation and private groups.

What to know first

Bronze package caps seats at 1,000.
Silver package caps seats at 2,000.
Gold package caps seats at 3,000.

Limits

The free plan includes core annotation, private groups and self-service support. It does not list LMS integration among its included features.

Plans

Plan	Billed and limits	Price
Free	Per student/yearly · Core annotation · Private groups · Self-service support	Free
Custom solution	Contact sales for a custom solution · Custom solution; page does not specify features or price	On request
Bronze	Per student/yearly · Core annotation · LMS integration · Up to 1,000 user seats · Partner workshops · One annual training session · Standard email support	On request
Silver	Per student/yearly · Core annotation · LMS integration · Up to 2,000 user seats · Advanced analytics · Auto-grading · Bronze support features · Hypothesis Academy	On request
Gold	Per student/yearly · Silver features · Up to 3,000 seats · Unlimited training · Dedicated customer success manager · Premium support · Hypothesis Academy · Quarterly check-ins	On request

As web.hypothes.is lists them, read 15 Oct 2026. The maker's own page has the final word.

Getting started

Visit https://web.hypothes.is/.
Create a free account for personal use and collaboration.
Use the web app, or add the Chrome extension on Chrome or another Chromium browser.
In Firefox or Safari, use the bookmarklet.

Verdict

Hypothesis brings annotations and discussion into course materials, with both personal use and institutional LMS integrations listed. Check the seat limits and package details when considering an institutional rollout.

Questions

Is Hypothesis free?

Yes. The Free plan costs nothing, billed per student/yearly, and includes core annotation, private groups and self-service support.

Which platforms can I use?

Hypothesis offers API and web access, plus an extension. The web app works with a Chrome extension on Chrome and other Chromium browsers, or a bookmarklet in Firefox and Safari.

Which course platforms does it integrate with?

Hypothesis lists Canvas, Blackboard, Moodle, D2L Brightspace and Sakai integrations through LTI 1.3. Annotations can sync with LMS gradebooks, including Canvas SpeedGrader.

What content can I annotate?

Supported content includes web pages, PDFs, EPUB files, YouTube videos, and content from VitalSource and JSTOR.

Can I export annotations?

Yes. Export formats are JSON, plain text, CSV and HTML; JSON import is also supported.

Who makes Hypothesis?

The site identifies the company as Annotation Unlimited, PBC. The project was founded as an open-source project in 2011.

Facts from Hypothesis's own pages

Additional integrations: Hypothesis says its annotations sync with LMS gradebooks, including Canvas SpeedGrader. · web.hypothes.is, 30 Sept 2026
Analytics: The LMS reporting dashboard provides annotation counts and engagement information across assignments and courses. · web.hypothes.is, 15 Oct 2026
Annotation features: Users can create annotations, private highlights, page notes, and threaded replies, and add tags to annotations. · web.hypothes.is, 30 Sept 2026
Annotation types: The service supports highlights, anchored annotations, page notes, threaded replies, tags and private, public or group visibility. · web.hypothes.is, 15 Oct 2026
API: The public API supports authentication plus creating, updating, deleting, searching and moderating annotations and managing users and groups. · web.hypothes.is, 15 Oct 2026
Auto-grading: The paid package descriptions include automatic grading based on student annotation activity and LMS gradebook synchronization. · web.hypothes.is, 15 Oct 2026
Browser access: The free web app can be used with a Chrome extension on Chrome and other Chromium browsers, or a bookmarklet in Firefox and Safari. · web.hypothes.is, 30 Sept 2026
Chrome distribution: The Chrome Web Store listing reports approximately 300,000 users and identifies Annotation Unlimited PBC as publisher. · chromewebstore.google.com, 15 Oct 2026
Company: The site footer identifies the company as Annotation Unlimited, PBC, and the About page says the project was founded as an open-source project in 2011. · web.hypothes.is, 30 Sept 2026
Company location and founding: LinkedIn lists headquarters in San Francisco, California and a 2011 founding year. · linkedin.com, 15 Oct 2026
Company scale: LinkedIn lists Hypothesis as a privately held education company with 11–50 employees. · linkedin.com, 15 Oct 2026
Compliance: Hypothesis says it has completed a Cloud Security Alliance CAIQ assessment and documents SOC compliance, and it provides a HECVAT response for higher education customers. · web.hypothes.is, 30 Sept 2026
Developer authentication: Users can create an API token at the developer account page, while OAuth authorization and token endpoints support integrated clients. · web.hypothes.is, 15 Oct 2026
Developer repositories: Hypothesis publishes public repositories for the annotation service, client, browser extension, PDF viewer, proxy, LMS app and WordPress plugin. · github.com, 15 Oct 2026
Documentation depth: The help center lists 37 annotation articles, 47 public-web articles and 124 LMS articles, plus installation and troubleshooting guides. · web.hypothes.is, 15 Oct 2026
Education focus: Hypothesis describes its institutional audience as colleges and universities, faculty and instructors, and students. · web.hypothes.is, 30 Sept 2026
Founded: 2011 · web.hypothes.is, 23 Sept 2026
Free personal use: Hypothesis says a free account is available for personal use and collaboration. · web.hypothes.is, 30 Sept 2026
Gradebook workflow: Canvas users can access student annotations through SpeedGrader, and the LMS app can synchronize annotation grades. · oit.colorado.edu, 15 Oct 2026
Image annotation: Image annotations let users place pins or area selections on visual material such as diagrams, charts and scanned PDFs. · web.hypothes.is, 15 Oct 2026
Independent finding: LMS workflow: The University of Colorado assessment found Hypothesis operates as an LTI integration with an annotation sidebar and Canvas SpeedGrader access. · oit.colorado.edu, 15 Oct 2026
Independent praise: collaboration: The University of North Texas guide reports that annotations can support collaborative discussion, peer review and inclusion of links, images and GIFs. · blogs.library.unt.edu, 15 Oct 2026
Independent praise: learning outcomes: Washington University’s teaching center cites research linking social annotation with better critical thinking, metacognition, reading comprehension and reading motivation. · ctl.wustl.edu, 15 Oct 2026
Legal maker: The service terms identify the contracting company as Annotation Unlimited, PBC. · web.hypothes.is, 15 Oct 2026

Where Hypothesis stands on Freedom251

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