HARPA AI vs Merlin
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
AI tool · Freemium
A Chrome extension combining AI chat with web automation, page monitoring and custom commands.
AI tool · Freemium
A browser extension giving access to several AI models on any page, for summarising, writing and chat.
The short answer
Choose HARPA AI if you need…
- Automating repetitive browser tasks
- Monitoring page changes
Choose Merlin if you need…
- Summarising pages and YouTube videos
- Multi-model chat in the browser
Side-by-side
| HARPA AI | Merlin | |
|---|---|---|
| Type | Plugins & extensions · AI browser extensions | Plugins & extensions · AI browser extensions |
| Price | Freemium | Freemium |
| Platforms | Chrome | Chrome, Web, iOS, Android |
| Works with | Chrome | Chrome, Gmail |
| Hands-on tested by us | Not yet | Not yet |
| Last checked | 2026-10-29 | 2026-10-29 |
What each one is
HARPA AI
A Chrome extension combining AI chat with web automation, page monitoring and custom commands. Uniquely automation-focused. Setup takes effort to get real value.
Merlin
A browser extension giving access to several AI models on any page, for summarising, writing and chat. Handy all-in-one sidebar. It can read the pages you visit, so review its permissions.
Best for
HARPA AI
- Automating repetitive browser tasks
- Monitoring page changes
Merlin
- Summarising pages and YouTube videos
- Multi-model chat in the browser
Strengths
HARPA AI
- AI chat on any page
- Custom automation commands
- Price and page monitoring
- Bring-your-own-key
Merlin
- Sidebar chat with multiple models
- Page and video summaries
- Writing help in text fields
Frequently asked questions
What is the difference between HARPA AI and Merlin?
HARPA AI: A Chrome extension combining AI chat with web automation, page monitoring and custom commands. Merlin: A browser extension giving access to several AI models on any page, for summarising, writing and chat. HARPA AI suits automating repetitive browser tasks, while Merlin suits summarising pages and youtube videos.
Are HARPA AI and Merlin free?
HARPA AI: Freemium. Merlin: Freemium.
What are other alternatives to HARPA AI and Merlin?
Other options people compare them with include MaxAI, Monica, Sider.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.