MarkLayer

Free Hypothesis alternatives

By Vadym Rusin · Last updated: March 2026

Looking for a Hypothesis alternative? Hypothesis is already free and open source, so the question is usually: which tool fits my use case better. Text-based scholarly annotation (Hypothesis) or visual annotation with drawings, arrows, and pinned comments (MarkLayer)?

Bottom line

MarkLayer is the right Hypothesis alternative if you need visual annotation. Drawings, arrows, comments pinned anywhere on the page. Diigo is a freemium hybrid. Markup.io and Pastel are paid visual-feedback alternatives. Hypothesis itself remains the right tool for scholarly text annotation.

Hypothesis alternatives compared

OptionPriceBest for
MarkLayerFree. No tiers, no seatsVisual feedback on UI, design, and live web product. Not scholarly text.
DiigoNot trackedPersonal research and bookmarking with light annotation.
Markup.ioNo free plan. Pro $79/month (unlimited users, 1 workspace); 14-day trialAgency project review on live websites.
AnnotateWebFree, no tiersQuick one-off annotations in your native language with no extension.

Prices as published by each vendor, checked August 2026, and read from each tool's owncomparison page. "Not tracked" means there is no comparison page for that option yet, so no price is quoted for it here.

Top free Hypothesis alternatives

1. MarkLayer

Free and open source, no install: paste a URL and annotate in your browser. Drawings, arrows, threaded comments pinned anywhere on the page. Real-time live cursors.

2. Diigo

Freemium browser bookmarking and annotation tool with text highlights and sticky notes. Closer to Hypothesis in shape.

3. Markup.io

Project-based visual feedback platform. Free tier with limits.

4. AnnotateWeb

Free bookmarklet-based annotation tool with multi-language support.

Frequently asked questions

Is MarkLayer like Hypothesis?
Both are free and open source, but they target different jobs. Hypothesis = scholarly text annotation with public groups. MarkLayer = visual annotation on any web page with drawings, arrows, and pinned comments.
Can Hypothesis annotate UI elements visually?
No. Hypothesis is text-anchored. Annotations attach to text selections, not pixels. For visual UI annotation (circling a button, arrowing a layout bug), MarkLayer is the right tool.
What's the closest Hypothesis-style tool for visual annotation?
There isn't a perfect 1:1 match. Hypothesis is fundamentally text-based. MarkLayer fills the visual-annotation gap with the closest spirit (free, open source, anchored to a page) but with pixel-level pinning instead of text-anchor.

Related comparisons

MarkLayer vs HypothesisFree Markup.io alternativesFree Pastel alternativesFree AnnotateWeb alternativesFree Jam.dev alternativesFree Marker.io alternativesFree Userback alternativesFree BugHerd alternativesFree Ruttl alternativesFree Usersnap alternativesFree stagewise alternativesFree Loom alternatives

Try MarkLayer

Paste any URL at marklayer.app and annotate the live page in your browser. No install, no account, no sign-up. Recipients of your share links don't need to install anything either.

Annotate a page

Or add the free Chrome extension for sites the web app cannot embed, such as pages behind a login.