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HARPA AI vs Monica

Two fact sheets from our own research, side by side — pricing, platforms, API access and status re-checked by us rather than quoted from the vendors. Both have a free tier. Only Monica ships a public API.

HARPA AIBrowser extension pairing chat models with web page automationMonicaMulti-model AI assistant living in a browser sidebar

Side by side

FactHARPA AIMonica
CategoryBrowser Extensions & CopilotsBrowser Extensions & Copilots
Pricing modelFreemiumFreemium
Public APINoYes
PlatformsWeb, Chrome ExtWeb, macOS, Windows, iOS, Android, API, Chrome Ext
CompanyHARPA AI TECHNOLOGIES LLCButterfly Effect Pte. Ltd.
Launched—2023
Last verifiedSep 6, 2026Sep 6, 2026

What our research says

HARPA AI

The strongest option if you want one extension that both discusses a page and acts on it, and it earns its price only if you actually build repeatable web workflows. For plain summaries and a chat sidebar, cheaper single-purpose extensions do the same job.

Pros

  • Commands run against the live DOM, so they work on pages behind a login
  • Bring-your-own-key and web-session modes keep running costs down
  • Registered EU entity with GDPR and ISO 27001 claims, unusual for an extension
  • Lifetime licence exists for people who refuse subscriptions

Cons

  • The command builder has a genuine learning curve
  • Token metering makes monthly spend hard to forecast
  • No developer API of its own, despite the automation positioning
  • Automations break when target sites change their markup

Monica

Worth it if you want one subscription that reaches GPT, Claude and Gemini from wherever you already are; pointless if you live inside a single vendor's app and are happy there. The value is the sidebar and the model switching, not the intelligence, which is all rented.

Pros

  • Genuinely wide model roster, including image and video models, under one credit pool
  • Extension plus desktop plus iOS/Android means the same history follows you across devices
  • Separate prepaid developer API at platform.monica.im if you want the same aggregation in code

Cons

  • Prices are only visible after loading the pricing app, and the tier names have already shifted once (Unlimited became Max)
  • Advanced credits reset monthly, so heavy image or video use burns a Pro plan fast
  • You are a reseller's customer — outages, rate limits and model deprecations arrive second-hand
  • monica.cn is a separate China-market build run by a different legal entity, which confuses support and privacy expectations

Which one fits

Choose HARPA AI if you need

  • Sales and research work that repeats the same extract-then-summarise loop across many pages
  • People who prefer bringing their own model API keys over another per-seat AI subscription
  • Watching pages for price or stock changes and firing alerts

Choose Monica if you need

  • People who compare answers across GPT, Claude and Gemini without paying three subscriptions
  • Reading and summarising foreign-language pages and PDFs in-place while browsing
  • Light users who want AI attached to the browser rather than in another tab

More comparisons

All HARPA AI alternatives →All Monica alternatives →Browse all Browser Extensions & Copilots →