AI sidebar and browser agent for reading, writing and research
AI sidebar and browser agent for reading, writing and research

Highlight any web text and query it with conversational AI, right on the page

This is our editors' assessment out of 5, not an average of user ratings. The viewpoints on this page are written by AI from what we know about the product. They are not customer reviews.
According to OpenAITools.app telemetry verified on 2026-11-11, MARK•R (mark-r.com) is an AI platform indexed under AI Assistant generating 43 monthly visits with a month-over-month traffic delta of -825 (-95.1%). Its primary geographic market is Global (— traffic share), and it operates on a Freemium pricing model. Top competing alternatives by monthly volume include Sider (2.64M visits/mo), Merlin AI (1.38M visits/mo), Monica (4.51M visits/mo).
Bypasses the endless tab-switching nightmare for long research docs.
Inline chat feels super natural once you get used to it.
Pro tier is a bit steep just for sidebar summaries.
Hit rate limits twice during deep PDF reviews.
AI-synthesized perspectives grounded in live site inspection, pricing structure, and category benchmarks — presented as editorial viewpoints rather than individual customer testimonials.
Selecting any passage on a page activates a dynamic icon and AI prompt field, so a question can be asked at the exact place you are reading rather than in a separate chat window.
Responses draw on the surrounding article or page, not just the highlighted fragment, which supports deeper questions about argument, terminology and implications.
Ask for an executive summary, a white-paper outline, slide talking points, suggested email replies or rewritten copy without leaving the browser.
Explain difficult terms, unpack technical or legal jargon and request simpler phrasing, which helps with dense academic, medical and financial material.
Free, Standard and Pro plans set different daily call limits, character allowances, output lengths and model access, with custom enterprise builds available.
MARK•R is a browser plugin built around one interaction: highlight text, then talk to it. Instead of copying a passage into a separate chatbot, you select it on the page and a small icon appears with an AI input field. Whatever you ask is answered inline, in the flow of reading, which keeps the source material and the conversation in the same visual context.
The distinguishing design decision is that MARK•R does not restrict itself to the highlighted fragment. It reads the surrounding page as well, so questions can be about the wider argument, the definitions used elsewhere in the article, or the assumptions behind a claim. That makes it more useful for interpretation and analysis than a simple selected-text rewriter, and it is the reason the plugin is marketed for research, study and content development rather than only for editing.
Practical applications cluster around comprehension and production. Students and researchers use it to unpack difficult concepts and terminology; professionals use it to clarify technical, legal or medical language; writers and marketers use it to generate summaries, outlines and alternative phrasing; and anyone drafting email in a browser can highlight the message they received and ask for suggested replies. Access is tiered: a free plan with a modest daily allowance of GPT-3.5 calls, paid Standard and Pro plans that add higher limits and GPT-4, and custom builds for organisations. The published plan structure references GPT-3.5 and GPT-4, so newer model options may not be available on this tool.
Highlight a difficult paragraph in a journal article or study and ask for a plainer explanation, a definition of the terminology, or the assumptions behind the claim.
Highlight contracts, standards, industry reports or financial disclosures and query acronyms and specialist concepts without leaving the source document.
Request an executive summary, a white-paper outline or slide talking points from material you are reading, then iterate on the phrasing directly where you found it.
Highlight an incoming email or marketplace message in your browser and ask MARK•R to suggest responses before you start typing.
Side-by-side telemetry comparison of competing AI tools in the same primary category
| Rank | AI Tool | Monthly Visits | MoM Growth | Direct traffic share | Pricing | Head-to-Head |
|---|---|---|---|---|---|---|
| ● | MARK•R | 43 | -95.1% | 37% direct | Freemium | Current |
| 1 | Sider | 2.64M | -10.6% | 64% direct | Freemium | vs Sider |
| 2 | Merlin AI | 1.38M | +13.1% | 50% direct | Freemium | vs Merlin AI |
| 3 | Monica | 4.51M | -11.3% | 55% direct | Freemium | vs Monica |
| 4 | Glasp | 889.56K | -14.1% | 45% direct | Freemium | vs Glasp |
| 5 | Chippy | 2.99K | +29.6% | 42% direct | Freemium | vs Chippy |
| 6 | Locus | 615 | -85.1% | 39% direct | Freemium, Free Trial | vs Locus |
AI sidebar and browser agent for reading, writing and research
AI sidebar and browser agent for reading, writing and research
One-click AI assistant for browsing, writing and research
One-click AI assistant for browsing, writing and research

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All-in-one AI assistant across web, browser, desktop and mobile
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One browser agent that combines every major AI model with web automation
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An AI copilot in your browser for reading, summarizing and questioning anything on the page.
An AI copilot in your browser for reading, summarizing and questioning anything on the page.