Reviewed by the NexaToolkit team · Last reviewed June 2026. We tested 20 and kept the few that earn a slot; more than 2–3 active extensions just compete for resources. NexaToolkit may earn a commission from links on this page — it never changes what we recommend.
AI Chrome extensions put a model one click away inside whatever page you’re on — summarize an article, rewrite an email, ask a sidebar without switching tabs. The catch: install too many and they fight for memory and attention. The right move is one all-in-one sidebar plus a specialist or two. Here are the extensions worth installing in 2026, with real prices.
All-in-one sidebars: Monica and Sider
Monica (free tier, $12/month) puts Claude, GPT, and Gemini in one sidebar — the best all-rounder. Sider (free, Basic $8.99, Pro $12.99, Unlimited $24.99) is the close rival: summarize pages, rewrite text, translate, and draft replies from the sidebar. Pick one as your hub.
Writing: Grammarly
Grammarly (free, Premium $12/month) is the most-used writing extension — in 2026 it does full sentence rewrites and tone shifts, not just grammar, everywhere you type. Compose AI (freemium) adds autocomplete for emails.
Research: Perplexity
The Perplexity extension (free; Pro $20/month) gives sourced answers and page summaries on demand — the research companion to your sidebar. Glasp (free) handles highlighting and summarizing.
Power automation: HARPA AI
HARPA AI (freemium) is the kitchen-sink option — web automation, scraping, monitoring, and YouTube summaries in one. Powerful but heavy; install only if you’ll use the automation.
AI Chrome extensions compared
| Extension | Price | Best for |
|---|---|---|
| Monica | Free / $12/mo | All-in-one sidebar |
| Sider | $8.99–$24.99/mo | Sidebar (summarize/translate) |
| Grammarly | Free / $12/mo | Writing everywhere |
| Perplexity | Free / $20/mo | Sourced research |
| Glasp | Free | Highlight + summarize |
A real scenario
A lean, fast browser setup: Monica (free or $12) as the all-in-one sidebar, Grammarly (free) for writing, and Perplexity (free) for research — $0–$12/month and three extensions that don’t overlap. Resist installing ten; keep it to 2–3 active or they slow the browser and clutter every page. Most people never need to pay beyond Monica’s $12 sidebar.
Frequently asked questions
What’s the best AI Chrome extension?
An all-in-one sidebar — Monica (free/$12) or Sider ($8.99+) — plus Grammarly for writing and Perplexity for research. That trio covers most needs without slowing your browser.
How many AI extensions should I run?
Two or three active, max. Beyond that they compete for memory and attention and the browser gets sluggish.
Are free AI extensions good enough?
Often yes — Grammarly, Perplexity, and Glasp have strong free tiers, and Monica/Sider offer capable free sidebars. Pay only when you hit daily limits.
More: see our AI productivity tools and AI research tools.
