Overview
Merlin is the most versatile AI browser extension, putting AI assistance on every webpage you visit. Unlike standalone AI tools that require switching tabs, Merlin works within your browser to help with whatever you are doing. Highlight text on any webpage and Merlin can summarize it, explain it, translate it, or rewrite it. When composing emails in Gmail or Outlook, Merlin can generate professional responses based on the email context. On LinkedIn, Twitter, or other social platforms, Merlin helps draft replies and posts. The extension supports multiple AI models including ChatGPT, Claude, Gemini, and Perplexity, letting you choose the best model for each task. Merlin also includes a PDF chat feature that lets you upload and discuss documents, and a writing assistant that works across all text fields on the web. For power users, custom shortcuts and tone settings let you tailor Merlin to your workflow. Pricing starts with a free tier (51 queries/day using basic models), Pro at $19/month for unlimited queries and access to premium models, and Team plans with centralized billing. Merlin has been installed by over 10 million users and is consistently rated as one of the most useful AI browser extensions available. The key advantage is convenience — instead of copying text between tabs, Merlin brings AI to where you already are.
4.4
Rating
1,890
Reviews
Yes
Free Tier
Merlin Key Features
Universal AI Assistant
AI assistance on any webpage — summarize, explain, translate, or rewrite highlighted text with one click.
Multi-Model Support
Access ChatGPT, Claude, Gemini, and Perplexity from a single extension. Choose the best model for each task.
Email Integration
Generate context-aware email replies in Gmail and Outlook. Merlin reads the email thread and drafts appropriate responses.
PDF Chat
Upload and discuss PDF documents with AI. Ask questions, request summaries, and extract information from documents.
Writing Assistant
Improve your writing across all web text fields with tone adjustment, grammar correction, and style suggestions.
Merlin Pros and Cons
Pros
- Works on every webpage — no tab switching needed
- Multiple AI models in one extension
- Summarize any article with one click
- Gmail and Outlook integration for email replies
- Generous free tier with 51 daily queries
- PDF chat for document analysis
Cons
- Can slow down browser performance sometimes
- Not all features work perfectly on every site
- Privacy concerns with browser-level access
- Premium model access requires Pro subscription
- Some users report inconsistent response quality
Merlin Pricing Plans
Plan
Subscription
Starting Price
Free / $19/mo (Pro)
Free Tier
Available
Merlin Review Verdict
Merlin earns a 4.4/5 rating based on 1,890 reviews and extensive hands-on testing. With pricing starting at Free / $19/mo (Pro), it's an excellent choice for Web research, Email composition, Content summarization. The free tier makes it easy to get started without commitment.
Try Merlin FreeMerlin Frequently Asked Questions
What is Merlin?
Merlin is a browser extension that brings AI to every webpage you visit. Summarize articles, compose emails, reply to social media, chat with PDFs, and access ChatGPT, Claude, and Gemini from any website with one click.
How much does Merlin cost?
Merlin starts at Free / $19/mo (Pro) on a subscription model. A free tier is available.
What is Merlin best for?
Merlin is best for Web research, Email composition, Content summarization, Social media, PDF analysis.
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