Gmail reverse conversation
AIFree
The add-on reverse emails in conversation view.
4.4343 reviews300K+
View Extension
Merlin AI
One AI assistant for summarising, writing and answering on any page.
4.88,800 reviews~900K+ usersAIBy Foyer Labs
Freemium
Reviewed by the Single Tab Browser editorial teamLast tested 2026-07-05Merlin AI screenshots
Overview
Merlin adds a keyboard-triggered AI sidebar to every page. It can summarise the current article, answer questions about it, draft replies in Gmail and generate social posts, switching between several underlying models.
Merlin AI is an AI Chrome extension from Foyer Labs with roughly 900K users on the Chrome Web Store. It holds a 4.8-star average across 9K ratings, which puts it among the better-reviewed options in its category. Pricing is freemium, listed at From $14.25/mo.
Merlin adds a keyboard-triggered AI sidebar to every page. It can summarise the current article, answer questions about it, draft replies in Gmail and generate social posts, switching between several underlying models.
The trade-off is the usual one for an freemium extension: the free tier gets you the core feature and the paid tier unlocks the parts most people eventually want. With 900K users, complaints and fixes surface quickly, so check the review notes below before installing it alongside other AI extensions.
How to install and set up Merlin AI
- 1Open the Chrome Web Store listing for Merlin AI and click Add to Chrome, then Add extension.
- 2Pin the icon: click the puzzle-piece button in Chrome's toolbar, find it in the list and click the pin so it stays visible.
- 3Open the extension once and walk through its first-run screen — a AI extension usually asks which sites it may act on.
- 4Test it on a page you know well before relying on it for daily work.
- 5To remove it later, right-click the toolbar icon and choose Remove from Chrome, or use chrome://extensions.
Key features
Merlin adds a keyboard-triggered AI sidebar to every page.
Merlin adds a keyboard-triggered AI sidebar to every page.
It can summarise the current article, answer questions about
It can summarise the current article, answer questions about it, draft replies in Gmail and generate social posts, switching between several…
Who should use Merlin AI?
Generalists who want a single AI sidebar instead of five separate AI extensions.
Pricing
Merlin AI is freemium — From $14.25/mo. The free tier is usable for evaluation; compare paid tiers before committing a team.
Merlin AI alternatives
Extensions people compare with Merlin AI most often.
WPS PDF - Read, Edit, Fill, Convert, and AI Chat PDF with Ease
AIFree
Easy-to-use PDF tools to view, edit, convert, fill, e-sign PDF files, and more in your browser.
4.5188 reviews6M+
View Extension
Monica AI
AIFreemium
AI copilot for chat, translation and writing on any site.
4.932,200 reviews3M+
View Extension
Linguix: Grammar Checker and AI Writing App
AIFreemium
Improve your writing and create compelling content with Linguix grammar checker & rewriter.
4.5550 reviews20K+
View ExtensionSimilar extensions
AnyDoc Translator - Translate Web and PDF
AIFree
The ultimate AI translator for web, files, ebooks, academic papers, images, and text
Store stats not synced yet
View Extension
HARPA AI: Web Automation with ChatGPT, Claude, Gemini, Grok
AIFreemium
Free AI sidebar with ChatGPT, Claude, Gemini & DeepSeek. 100+ commands to automate, monitor prices, summarize & write.
4.73,200 reviews300K+
View Extension
Black Menu for Google™
AIFree
The easiest access to the Google universe with Gemini AI and sidebar support
4.63,800 reviews200K+
View ExtensionMonica AI
AIFreemium
AI copilot for chat, translation and writing on any site.
4.932,200 reviews3M+
View ExtensionWPS PDF - Read, Edit, Fill, Convert, and AI Chat PDF with Ease
AIFree
Easy-to-use PDF tools to view, edit, convert, fill, e-sign PDF files, and more in your browser.
4.5188 reviews6M+
View Extension
Brisk Teaching - AI that Works Where Teachers Work
AIFree
AI for teachers, right inside Google Docs, Classroom, YouTube, and more. Tell Brisk what you need and save 10+ hours a week.
4.7731 reviews1M+
View ExtensionFrequently asked questions
Is Merlin AI free?
It is a freemium extension with a listed price of From $14.25/mo. The free tier covers the core feature; paid tiers unlock the rest.
How many people use Merlin AI?
Roughly 900K Chrome users have it installed, and it holds a 4.8-star average from 9K ratings.
Is Merlin AI safe to install?
Merlin AI is published on the official Chrome Web Store by Foyer Labs, so it passes Google's review. Check the permissions it asks for on install and prefer the store listing over third-party mirrors.
What are the best Merlin AI alternatives?
The alternatives page lists the closest AI extensions ranked by installs and rating, with a head-to-head comparison for the top pick.
Related extensions to Merlin AI
Picked from the AI category and the tags ai, summariser, assistant — jump straight to the alternatives and head-to-head pages people open next.
Best AI Chrome extensionsGmail reverse conversation alternativesThe add-on reverse emails in conversation view.WPS PDF - Read, Edit, Fill, Convert, and AI Chat PDF with Ease alternativesEasy-to-use PDF tools to view, edit, convert, fill, e-sign PDF files, and more in your browser.Monica AI alternativesAI copilot for chat, translation and writing on any site.Linguix: Grammar Checker and AI Writing App alternativesImprove your writing and create compelling content with Linguix grammar checker & rewriter.Monica vs Merlin AIMonica or Merlin AI for an AI sidebar?Merlin AI vs PerplexityMerlin AI or Perplexity: which should I install?Monica vs PerplexityWhich AI extension gives sourced answers?Perplexity vs Zotero ConnectorPerplexity or Zotero Connector: which should I install?All AI extensionsEvery ai extension in the directory, ranked.
Compare Merlin AI with the obvious rivals
Side-by-side feature tables, pricing and a clear recommendation.
Monica vs Merlin AITwo all-in-one AI sidebars compared on model access, free quota and page context.Merlin AI vs PerplexityBoth are ai extensions people shortlist together for ai — see how ratings, install base, pricing and day-to-day use differ.Monica AI vs Merlin AIHead-to-head breakdown with real install and rating data.Perplexity vs Merlin AIHead-to-head breakdown with real install and rating data.Sidebar: ChatGPT, Bookmarks, GPT-4o | Meomni vs Merlin AIHead-to-head breakdown with real install and rating data.Merlin AI alternativesRanked replacements if Merlin AI is not the right fit.All comparisonsThe full compare hub, grouped by category.