Reason Lens

Think deeper about what you read. Break down ideas, find hidden assumptions, and evaluate claim strength.

ReasonLens is a critical thinking assistant for the web that helps users better understand selected text from webpages, documents, and PDFs by breaking down ideas, finding hidden assumptions, and evaluating claim strength. To use ReasonLens, users highlight a sentence or paragraph and click the Ask ReasonLens button, or right-click selected text and choose Analyze with ReasonLens from the context menu. The extension does not analyze page content automatically; analysis only starts after the user selects text and chooses to analyze it. ReasonLens provides three reasoning-focused analysis modes: Break it Down, which explains the selected text in simpler terms; Assumptions, which identifies hidden assumptions behind the selected text; and Claim Strength, which evaluates how strong or weak a claim appears. Users can save useful analyses in a local notebook for later review, and notebook entries are stored locally in Chrome storage. ReasonLens also supports Google Sign-In for account access, usage limits, and Free or Pro plan management. It is useful for reading articles, research, documentation, essays, reports, and online discussions where users want to think more clearly about the text they are reading.