Criterion Gemini Notebook (formerly NotebookLM)Perplexity
CategoryAI Research ToolsAI Research Tools
In one sentenceGoogle's source-grounded research notebook, renamed from NotebookLM to Gemini Notebook in July 2026.An AI answer engine that searches the web and cites sources, with access to models from several providers on paid plans.
Problem it solvesMaking sense of many long documents is slow, and general chatbots may answer from outside your material.Saves time finding and checking information by returning cited answers instead of a list of links.
Free planYesYes
Developer APINoYes — docs
Open sourceNoNo
PlatformsWeb, iOS, Android, Gemini appWeb, iOS, Android, Comet browser
Pricing (summary)Free with a Google account (100 notebooks, 50 sources each). Higher limits come with Google AI Plus, Pro and Ultra subscriptions; Google's plan page did not display prices in the fetched version, so check Google One for current amounts.
Checked 2026-10-23		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
  • Strong grounding in user-provided sources
  • Free tier is usable for real projects
  • Integrated with Google's Gemini ecosystem
  • Strong focus on citations
  • Multi-provider model access
  • Published enterprise limits
Limitations
  • Free tier capped at 100 notebooks and 50 sources per notebook
  • Code execution limited to higher paid tiers at launch
  • Name change may cause confusion with notebooks inside the Gemini app
  • Free plan has tight Pro Search and Research limits
  • Pro limits described as 'average use' rather than numbers
  • API billed separately from subscriptions