Reference Guide

AI Search

Comparing the AI-powered search engines that have replaced "ten blue links" for many users. Citation quality, research depth, real-time access, privacy, and where each tool fits.

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A purpose-built answer engine that synthesizes web sources into cited summaries. Founded as an AI-native alternative to Google, Perplexity leads on citation quality, source transparency, and research workflows. Now bundled with Comet, an AI browser that runs agentic tasks across tabs.

  • Free: Limited Pro searches per day, basic models, standard citations
  • Pro $20/mo (or $200/yr): Unlimited Pro searches, model picker (GPT-5, Claude Opus 4.7, Gemini 3 Pro, Grok 4), file uploads, image generation, $5/mo API credits
  • Max $200/mo: Unlimited access to top-tier models with no rate caps, video generation (15 clips/mo), expanded Spaces and file storage
  • Enterprise Pro $40/seat/mo: SSO, team Spaces, admin controls, data privacy, shared repositories
  • Enterprise Max $325/seat/mo: Everything in Enterprise Pro plus o3-pro and Claude Opus 4 access, 5,000 files per Space, 10,000 files in user repository, audit logs and SCIM (50+ seats)
  • Spaces: Project-scoped collections of files, web sources, and chat history — great for ongoing research
  • Comet browser: AI-native browser (iOS, Android, desktop) with autonomous tab agents, page summarization, form filling, and Comet Spaces
  • Sonar API: Developer access at $3/M input + $15/M output (Sonar Pro) or flat $5 per 1,000 requests (Search API). Citation tokens are no longer billed in 2026.

Limitations: No native Microsoft 365 or Google Workspace integration. Pro tier's $5 API credit is barely enough to test with — production use requires prepaid credits. Source quality depends heavily on which sites Perplexity has crawled or licensed; can occasionally over-rely on a single domain.

Answer EngineFree Tier

Two distinct AI experiences inside Google Search. AI Overviews are summarized answers with citations that appear above the traditional results — free for everyone. AI Mode is a separate conversational tab powered by Gemini 3 Pro with multimodal reasoning, follow-up questions, and Deep Search for expert-level research reports.

  • AI Overviews: Free, deployed to all Google users, appears above search results with inline links
  • AI Mode (free): Conversational mode with limited Gemini 3 Pro access, follow-up questions, Deep Search at lower tier
  • Google AI Pro $19.99/mo: Higher AI Mode access to Gemini 3 Pro, 2 TB Drive storage, Gemini in Workspace apps, NotebookLM Pro, Deep Research
  • Google AI Ultra $249.99/mo: Highest tier of Gemini 3 Pro in AI Mode, Veo video generation, 30 TB storage, Personal Intelligence features, agent mode
  • Deep Search: Query fan-out runs hundreds of background searches, reasons across the results, and writes a fully cited expert report — one of the strongest research modes available
  • Personal Intelligence: Optional premium feature that grounds AI Mode in your Gmail, Calendar, Drive, and search history
  • Reach: The default search interface for billions of users — AI Overviews are the most-seen AI search experience in the world

Limitations: AI Overviews show on a subset of queries and can be inconsistent — they sometimes hallucinate or surface low-quality sources, and Google has retracted multiple high-profile bad answers. AI Mode is improving fast but still lags Perplexity on tight citations and source linking. Deep Search and Personal Intelligence require paid tiers.

Default SearchFree Tier

Real-time web search baked into ChatGPT. Available across Free, Plus, Team, Edu, and Enterprise tiers (and to logged-out users). Responses include inline citations you can hover or click for the source. ChatGPT also offers richer shopping, conversational browsing, and image-based product search.

  • Free: ChatGPT Search included; rate-limited but unmetered for basic web queries
  • Plus $20/mo: Higher rate limits, GPT-5 / o-series reasoning access, Deep Research, custom GPTs, voice mode
  • Business $25/seat/mo (annual) or $30 monthly: Team workspace, admin controls, data privacy (no training on your data), Company Knowledge connectors
  • Enterprise (custom): SSO, audit logs, advanced data controls, larger context windows, priority access
  • Inline citations: Hover or click footnote-style citations to see source URL and snippet
  • Shopping & visual search: Rich product cards, side-by-side comparisons, upload an image to find similar items
  • Company Knowledge: Connectors to Google Drive, SharePoint, Slack, GitHub, etc. so search results blend internal + web sources
  • Deep Research: Multi-step research mode that produces long-form cited reports (Plus and above)

Limitations: Not a dedicated "search engine" UI — you have to go through chat. Citation density is lower than Perplexity. Real-time freshness is good but lags Perplexity and Grok for breaking news. Web search can be silently disabled depending on which tool the model picks.

Chat + SearchFree Tier

xAI's assistant with first-class access to X (formerly Twitter) data. Excels at real-time event analysis, public sentiment, and trending narratives because it indexes the firehose of posts. DeepSearch produces cited multi-source research reports; Big Brain Mode runs longer reasoning chains.

  • Free: ~10 prompts per 2 hours, basic Grok 4.1 access, limited DeepSearch
  • X Premium $8/mo: Bundled with X social features and ad-light experience, modest Grok access
  • X Premium+ $40/mo: Higher Grok limits plus ad-free X
  • SuperGrok $30/mo (or $300/yr): Full Grok suite, expanded DeepSearch, Big Brain Mode, image and video generation
  • SuperGrok Heavy $300/mo: Exclusive Grok 4 Heavy multi-agent architecture for the hardest reasoning tasks
  • Grok Business $30/seat/mo: Team workspace, data privacy, no training on org data
  • API: Grok 4.1 Fast at $0.20/M in + $0.50/M out; Grok 4 at $3/M in + $15/M out; web tool calls add ~$0.015–$0.025 per query
  • 2M token context: Useful for document-heavy work and long research sessions

Limitations: Tone and editorial guardrails are looser than competitors — can be a feature or a liability depending on use case. Web search beyond X is solid but not as broad as Perplexity. Heavy reliance on X data means weaker results on topics with little social conversation. Enterprise feature set is younger than OpenAI's or Google's.

Real-time / SocialFree Tier

Microsoft's AI search experience available through Bing and the Copilot app. Cross-checks information across web sources and produces curated answers with prominent citations. Tightly integrated with Microsoft 365 for enterprise tenants — the same Copilot can search the web, your SharePoint, your inbox, and your Teams chats.

  • Free (Bing Copilot Search): Web AI search with citations, image generation, dedicated Search mode within Copilot
  • Copilot Pro $20/mo: Priority access in peak times, advanced models, Copilot in Microsoft 365 consumer apps (Word, Excel, etc.)
  • Microsoft 365 Copilot $30/seat/mo: Enterprise Copilot with grounding in your tenant data — SharePoint, OneDrive, Teams, Outlook, plus the web
  • Citations & aggregated sources: Recent Fall Release made citations more prominent and clickable, with an option to view aggregated sources behind an answer
  • Cross-site reasoning: Copilot Search reads multiple sources and reconciles conflicts before answering
  • Adaptive responses: Concise answers for simple queries, in-depth summaries for complex ones
  • Edge integration: Built into the Edge browser and Windows 11 with sidebar Copilot access

Limitations: Bing's organic index lags Google's for long-tail queries. Microsoft has been criticized for aggressively pushing Copilot in Bing search results when users search for ChatGPT or Gemini. The strongest enterprise features sit behind M365 Copilot — if your org isn't on Microsoft 365, you lose most of the differentiation.

Enterprise / M365Free Tier

AI search platform that lets you pick the model behind every query — GPT-5, Claude Opus, Gemini 3 Pro, and others all from one interface. Stronger privacy posture than the platform players (no behavioral ad tracking) and a serious developer API for grounding agentic apps in web data.

  • Free: Unlimited Express AI model access, basic search, limited image generation
  • Pro $20/mo (or $15/mo annual at $180/yr): Access to GPT-5, Claude Opus, Gemini 3 Pro, file uploads, larger context windows, Deep Research mode
  • Search modes: Quick, Dynamic, and Deep Search — pick depth based on the query
  • Source constraints: Limit a search to specific domains or upload custom documents to ground answers
  • Express Agent API $11/mo: Lightweight agent API for developers
  • Deep Search API: Pay-as-you-go at ~$15 per research call with $100 in free credits
  • Enterprise (custom): Private data sources, team management, custom AI agents
  • Privacy: No tracking for targeted advertising; explicit privacy mode available

Limitations: Smaller user base means less product polish than Perplexity or Google. Web index is competitive but not as deep as Google or Bing. Brand recognition is the lowest of the six tools here, which can matter when sharing cited results with clients.

Multi-ModelFree Tier