Criterion Microsoft Copilot Perplexity
CategoryAI Chatbots & AssistantsAI Research Tools
In one sentenceMicrosoft's AI assistant, free on its own and built into Word, Excel, PowerPoint and Outlook through Microsoft 365 plans.An AI answer engine that searches the web and cites sources, with access to models from several providers on paid plans.
Problem it solvesBrings AI help into the Office apps people already use for documents, spreadsheets, slides and email.Saves time finding and checking information by returning cited answers instead of a list of links.
Free planYesYes
Developer APINoYes — docs
Open sourceNoNo
PlatformsWeb, Windows, iOS, Android, Microsoft 365 appsWeb, iOS, Android, Comet browser
Pricing (summary)The Copilot app is free with limited usage. Microsoft 365 Personal ($9.99/month), Family ($12.99/month) and Premium ($19.99/month) add Copilot in Office apps. Businesses can buy bundles with Copilot or a Copilot Business add-on per user.
Checked 2026-10-19		Free costs nothing. Pro is $20/month or $200/year, Max $200/month or $2,000/year, and Enterprise Pro starts at $40 per seat per month. The Sonar API is billed separately per token plus per-request fees.
Checked 2026-10-19
Strengths
  • Deep Office integration
  • Bundles storage and Office apps
  • Business add-on priced per user
  • Strong focus on citations
  • Multi-provider model access
  • Published enterprise limits
Limitations
  • Models used per plan are not named on pricing pages
  • Family plan AI features are owner-only
  • No AI features in Microsoft 365 Basic
  • Free plan has tight Pro Search and Research limits
  • Pro limits described as 'average use' rather than numbers
  • API billed separately from subscriptions