Why Your Browser Needs AI Extensions in 2026
I spend about 10 hours a day in Chrome. Email, research, writing, coding – it all happens in browser tabs. So when AI extensions started getting actually good in late 2025, I went on a testing spree. Installed 19 different ones over two months.
Most were garbage. Some slowed my browser to a crawl. A few were just ChatGPT wrappers with a markup. But seven of them stuck. These are the ones I still use daily, and they’ve changed how I work in ways I didn’t expect.
Quick note: I’m not including extensions that just give you a chatbot sidebar. Every AI company has one of those now. I’m focusing on extensions that actually DO something useful without you having to write prompts.
1. Sider AI – Best All-in-One AI Sidebar
Sider started as a simple ChatGPT sidebar extension back in 2023. It’s grown into something much more useful since then.
What makes it different from other sidebar extensions: it connects to multiple AI models (GPT-4o, Claude, Gemini) and lets you switch between them mid-conversation. You highlight text on any page, and Sider pops up with options to summarize, translate, explain, or rewrite. No prompt engineering needed.
The reading mode is where I get the most value. Open a long article, click Sider, and you get a summary with key points pulled out. I’ve been using this for research and it cuts my reading time by maybe 40%. Not the “10x productivity” some people claim, but 40% is still real.
Pricing
Free tier gives you 30 queries per day. Pro is $10/month for unlimited queries across all models. There’s a yearly plan at $8/month if you commit.
What I don’t like
The extension icon placement is annoying – it pops up whenever you select text, even when you’re just copying a URL. You can disable this in settings but the default behavior is pushy. Also, the free tier got more restrictive in February 2026.
2. Monica AI – Best for Writing Assistance
Monica does a lot of the same things as Sider, but its writing features are noticeably better. The compose tab lets you draft emails, social posts, and replies directly in the extension without switching tabs.
Here’s the thing about Monica that sold me: it reads the context of the page you’re on. If you’re looking at a LinkedIn post, the reply suggestions actually match the tone and topic. If you’re on Gmail, the email drafts reference the thread you’re replying to. It’s not just generating generic text.
I tested it against dedicated AI writing tools and for short-form content (emails, social replies, quick summaries), Monica holds its own. For long articles, you still want a proper writing tool.
Pricing
Free: 40 daily queries. Pro: $9.90/month. They also have a $19.90/month plan that adds GPT-4o and Claude access.
Standout feature
The “Art” tab generates images right in your browser. Quality is decent for social media thumbnails and blog post headers. Not Midjourney-level, but fast and convenient when you need something quick. If you need more serious image generation, check out our list of the best AI image generators.
3. Merlin AI – Best for Research and Summarization
Merlin used to be called “ChatGPT for Google” and it still does that – showing AI answers alongside your search results. But the 2026 version does a lot more.
The YouTube summarizer is legitimately great. Click the Merlin icon on any YouTube video and you get timestamped summaries. I watch (or rather, skim) about 15 tech videos per week this way. A 40-minute conference talk becomes a 2-minute read with timestamps so I can jump to the parts that matter.
It also works on PDFs, which is where it beats Sider for my workflow. Upload or open a PDF in Chrome, and Merlin lets you chat with it. For anyone who reads research papers or long documentation, this alone justifies the extension. See our roundup of AI summarizer tools for more options in this space.
| Feature | Sider | Monica | Merlin |
|---|---|---|---|
| YouTube summaries | Basic | No | Timestamped |
| PDF chat | Yes | Yes | Best-in-class |
| Multi-model | GPT-4o, Claude, Gemini | GPT-4o, Claude | GPT-4o, Claude, Llama |
| Free daily queries | 30 | 40 | 51 |
| Writing tools | Good | Best | Basic |
4. Glasp – Best for Highlighting and Knowledge Management
Glasp isn’t a chatbot extension. It’s a web highlighter with AI superpowers, and honestly it’s the one on this list I recommend most often.
You highlight passages on any webpage. Glasp saves them, organizes them, and uses AI to find connections between your highlights across different articles. After a month of using it, I had a searchable knowledge base of everything I’d read online. The AI summary feature takes all your highlights from a page and generates a coherent summary.
The social aspect is interesting too. You can see what other Glasp users highlighted on the same article. It’s like seeing the marginalia in a library book, except the notes are from people in your field.
For anyone doing serious research, content creation, or just trying to remember what they read last week – Glasp fills a gap that bookmarks never could. It pairs well with note-taking workflows, especially if you use something from our best AI note-taking apps list.
Pricing
Free for basic highlighting and AI summaries. Premium is $12/month and adds unlimited AI features, advanced search, and export to Notion/Obsidian.
5. Harpa AI – Best for Browser Automation
Harpa is the power-user pick on this list. It combines AI chat with browser automation, so you can create workflows that monitor pages, extract data, and perform actions automatically.
Real example from my workflow: I set Harpa to monitor a competitor’s pricing page. When the price changed, Harpa detected it and sent me an alert. Setting this up took about 3 minutes. No code, no Zapier, no separate monitoring tool.
The page-aware AI commands are solid too. You can tell Harpa “extract all email addresses from this page” or “summarize the comments section” and it works because it can actually read the DOM, not just the visible text. If you’re into automating repetitive tasks, also check our list of task automation tools for desktop-level solutions.
What makes it different
Harpa runs AI models locally when possible (using WebLLM), which means some features work without an API key and without sending your data to external servers. Privacy-conscious users will appreciate this.
Pricing
Free tier is generous – most features work. Pro starts at $15/month for advanced automation and monitoring features.
6. Waspnest (Perplexity Extension) – Best for Quick Answers
Perplexity launched their Chrome extension in late 2025, and look – if you already use Perplexity as your AI search engine, this is a no-brainer install.
Right-click any text on a page and select “Ask Perplexity.” That’s it. You get sourced answers in a popup without leaving your current tab. The answers include citations, which is something most other extensions skip.
I use this probably 8-10 times per day for fact-checking while writing. Someone claims a statistic in a blog post? Highlight, right-click, Perplexity. In 3 seconds I know if it’s accurate and where the original data came from.
Pricing
Free with a Perplexity account. Pro features ($20/month Perplexity Pro subscription) give you GPT-4o and Claude-powered answers in the extension.
7. Compose AI – Best Free AI Autocomplete
Compose AI does one thing: it autocompletes your sentences as you type, anywhere in Chrome. Gmail, Google Docs, Twitter, Slack – wherever there’s a text field, Compose AI suggests completions.
Think of it like GitHub Copilot but for regular writing. You start a sentence, and a gray suggestion appears. Hit Tab to accept. It learns your writing style over time, so the suggestions get more relevant the longer you use it.
Honestly, I was skeptical. The concept sounds simple to the point of being useless. But after two weeks, I noticed I was typing maybe 30% faster on routine communications. Emails especially. The extension is particularly good at completing common professional phrases and matching the formality level of what you’ve already typed.
Pricing
Completely free. They monetize through a premium tier ($12.99/month) that adds rephrasing tools and longer completions, but the core autocomplete is free with no daily limits.
How I Tested These Extensions
I installed each extension individually first, then in combinations, across three weeks. Here’s what I measured:
- Memory usage: Chrome’s Task Manager showing per-extension RAM consumption
- Response speed: Time from click/highlight to getting a useful result
- Accuracy: Spot-checked AI outputs against source material for factual errors
- Privacy: Reviewed permissions and data policies
- Daily actual usage: Which ones I reached for naturally vs. forgot about
The memory thing matters more than people realize. Some AI extensions add 200-400MB of RAM usage. If you’re already running 30+ tabs (no judgment), that adds up fast. All seven extensions on this list stayed under 150MB in my testing.
Extensions I Tested But Didn’t Make the List
MaxAI – solid but too similar to Sider with a higher price point. UseChatGPT.AI – good concept but the free tier is too restrictive now. Tactiq – excellent for meeting transcription but too niche for a general list. WebChatGPT – was great in 2024 but hasn’t kept up with the competition.
Can You Run Multiple AI Extensions at Once?
Yes, but be selective. Running all seven from this list simultaneously added about 600MB of RAM and created some UI conflicts (multiple extensions trying to show popups when you highlight text).
My recommended combo: Glasp (always on for highlighting) + one general assistant (Sider OR Monica, not both) + Compose AI (lightweight, always-on autocomplete). That covers most use cases without the bloat. If you’re working on something research-heavy, swap in Merlin for the session.
FAQ
Are AI Chrome extensions safe to use?
Generally yes, but check the permissions. Any extension asking for “Read and change all your data on all websites” has broad access to your browsing. All extensions on this list request this permission because they need to read page content to work. Stick with established extensions that have clear privacy policies and large user bases.
Do AI Chrome extensions work with other browsers?
Most of them work on any Chromium-based browser – Edge, Brave, Opera, Vivaldi, Arc. Firefox support is hit or miss. Sider and Monica have Firefox versions. The others are Chrome/Chromium only.
Will these extensions slow down my browser?
They add some overhead, but less than you’d think. In my testing, individual extensions added 50-150MB of RAM. The bigger concern is UI clutter – multiple extensions all wanting to show popups and sidebars. Disable the ones you’re not actively using.
Can I use these for work without my company finding out?
Depends on your company’s IT policy. Some organizations block extension installs. Others monitor installed extensions. If you’re on a managed Chrome profile, check with IT first. On a personal browser on a personal device, that’s your call. Note that some extensions (like Monica and Sider) process text through external AI servers, which means sensitive work content leaves your machine.
Which one AI Chrome extension should I install first?
If you write a lot of emails and messages: Compose AI (free, lightweight, immediate value). If you do research: Merlin or Glasp. If you want an all-purpose AI assistant: Sider. Start with one, use it for a week, then decide if you need more.