Kagi
Performs ad-free private web search with user controls like Lenses and page summarization.
10 tools·Updated Nov 23, 2025
AI search engines combine conversational interfaces with web retrieval to provide synthesized answers backed by verifiable sources. Unlike traditional search that returns link lists, AI search engines like Perplexity, Bing Copilot, and Google AI Overviews write direct answers while citing references. This guide helps researchers, developers, students, and everyday users choose the best AI search engine based on accuracy, freshness controls, privacy stance, API access, and specific use cases from academic research to technical documentation lookup.
Performs ad-free private web search with user controls like Lenses and page summarization.
Generates conversational answers to search queries instead of providing a list of links.
Searches the web privately and provides AI-powered answers using its own independent index.
Generates an AI overview of a topic by summarizing web information and providing links in response to search queries.
Synthesizes information to deliver answers, connect ideas, and help users explore topics.
Exa API provides real-time web data to enhance AI applications, enabling efficient research and contextualization with reliable information.
Phind: A tool that helps find development solutions by utilizing natural language queries for efficient coding assistance.
Consensus is an AI academic search engine that provides insights from over 200M research papers, helping users find and understand scientifi...
Control your own search engine with you.com. Verify your connection to ensure secure access and personalized search results.
An AI search engine that combines large language models with traditional search engines to enhance information retrieval.
An AI search engine is a hybrid system that combines conversational AI with web retrieval to generate synthesized answers while displaying verifiable source citations. Unlike traditional search engines that present "ten blue links" for users to explore, AI search engines process your query, retrieve relevant information from across the web, and write a coherent answer with inline references you can verify.
Core capabilities include:
Who uses AI search engines:
Key differences from traditional search:
| Traditional Search | AI Search Engine |
|---|---|
| Returns ranked list of links | Writes synthesized answer with citations |
| User reads multiple pages | AI reads and summarizes for you |
| Good for exhaustive discovery | Good for quick understanding + verification |
Full control over operators (site:, filetype:) |
Conversational constraints (add context in plain English) |
| No interpretation | Interprets and connects information across sources |
When to use AI search vs traditional search:
AI search engines work best when you need fast, evidence-backed answers and plan to verify key claims by opening the cited sources. They excel at research workflows where understanding context matters more than finding every possible result. For content creation based on research, explore AI content generators and AI writing assistants.
AI search engines combine three key technologies to deliver synthesized answers with citations: retrieval systems, language models, and source grounding mechanisms.
AI search engines access web content through one of two approaches:
Own index (e.g., Brave Search, Kagi): Maintains an independent web crawler and index, similar to traditional search engines. Offers consistent ranking, privacy controls, and independence from third-party data. Index coverage is typically smaller than Google but focused on quality.
Meta-aggregation (e.g., Perplexity, Bing Copilot): Queries existing search APIs (Bing, Google) or crawls pages on-demand. Excels at fresh content and broad coverage without maintaining a full index. Perplexity, for example, uses PerplexityBot plus real-time fetchers to gather current information (Perplexity Crawlers).
Once relevant pages are retrieved:
Advanced systems support model selection (Perplexity Pro offers multiple model options) and follow-up refinement where the conversation context is maintained across queries.
Different engines handle recency differently:
AI search engines differ significantly in data handling:
Understanding how your chosen AI search engine retrieves, synthesizes, and handles data helps you evaluate trustworthiness and choose the right tool for sensitive research.
When comparing AI search engines, prioritize features that match your use case—research depth, privacy needs, technical capabilities, or everyday convenience.
What to look for:
Why it matters: Without verifiable citations, AI-generated answers risk hallucination or misrepresentation. Engines like Perplexity and Bing Copilot provide explicit source cards and allow expanding the full link list.
What to look for:
Why it matters: For journalism, market research, or technical troubleshooting, outdated answers waste time or mislead. Bing Copilot lets you set grounding windows; Perplexity performs on-demand fetches.
What to look for:
site: operator support or domain restrictionsWhy it matters: Constraining scope improves relevance. If you only trust .gov or .edu sources, or need code examples from official docs, domain filtering saves verification time.
What to look for:
Why it matters: Developers building agents or research tools need API access to ground LLMs. Exa offers search/crawl/extract endpoints; Perplexity provides a Search API with per-query pricing.
What to look for:
Why it matters: Research on sensitive topics (health, legal, financial) demands privacy. Ad-funded engines may track queries; paid or privacy-first engines don't.
What to look for:
Why it matters: If you live in Microsoft 365, Bing Copilot Search integrates natively. Google AI Overviews appear directly in SERPs. Standalone apps (Perplexity, Phind) work cross-platform.
What to look for:
Why it matters: For deep research, organizing threads and exporting references streamlines writing and citation management. Complement search with AI knowledge base tools for long-term information storage.
What to look for:
Evaluate features based on your primary workflow—casual browsing favors convenience and speed; scholarly research demands citation quality and corpus depth; API integration requires developer-friendly endpoints and clear pricing. For content optimization, consider pairing with AI SEO tools.
Selecting the best AI search engine depends on your role, workflow, privacy requirements, and willingness to pay for advanced features. Use this decision framework to match tools to your needs.
Researchers and Analysts
Developers and Technical Users
Students and Educators
Journalists and News Professionals
Privacy-Conscious Users
Enterprise and Microsoft 365 Users
Everyday Users (Casual Browsing, Shopping, How-To)
Free (no payment required):
Paid (unlock advanced features):
Pay-as-you-go API:
API and Developer Integration:
Customization and Control:
Academic and Scholarly:
Strongest privacy:
Enterprise-grade compliance:
Zero-retention model options:
Start with the free tier of 2-3 engines that match your role, test with real queries, and verify citation quality by opening the sources. Upgrade to paid plans when you hit limits or need advanced features like model selection or custom Lenses.
This evaluation is based on a structured methodology combining official documentation, hands-on testing, and third-party verification to ensure accuracy and reproducibility.
Primary sources:
Exclusions: I excluded tools without verifiable documentation or those that don't provide explicit source citations (pure chat interfaces without grounding).
I prioritized the following dimensions based on user needs identified in community discussions and professional use cases:
Citation Quality and Transparency (30%)
Freshness and Real-Time Data (20%)
Index Coverage and Approach (15%)
Privacy and Data Handling (15%)
Developer and API Access (10%)
Use Case Specialization (10%)
Citation verification:
Freshness validation:
Privacy claims:
API and developer experience:
What this evaluation does not cover:
Potential biases:
Handling conflicts:
All documentation, pricing, and feature verification accessed between November 18-20, 2025 (UTC). AI search is a rapidly evolving category; features, pricing, and availability may change. I recommend verifying current details on official websites before making decisions.
Citations link directly to official documentation or high-quality third-party sources. You can reproduce this evaluation by:
This methodology prioritizes evidence-based evaluation over subjective impressions, ensuring recommendations are grounded in verifiable facts.
The following table compares the top 10 AI search engines across key dimensions: indexing approach, citation quality, freshness controls, privacy stance, API access, and pricing. All information is verified from official documentation accessed November 18-20, 2025.
| Tool | Index Approach | Answer Style | Freshness & Time Controls | Model Options | Privacy & Compliance | API Access | Platform | Pricing | Best For |
|---|---|---|---|---|---|---|---|---|---|
| Perplexity AI | Meta over public web; PerplexityBot + on-demand fetcher | Answer cards with inline citations; follow-up threads | Real-time fetch; documented crawlers | Pro/Enterprise model choices (GPT-4, Claude, etc.) | SOC 2 report; documented data retention policies | API Platform (Answer/Sonar APIs, pay-as-you-go) | Web, iOS, Android, Chrome | Free; Pro $20/mo; Enterprise custom | Researchers, journalists needing fast, citation-rich answers |
| Bing Copilot Search | Grounded on Bing's own index | Summarized answer with expandable source list | Day/Week/Month recency control via Bing grounding | Microsoft models; system-managed grounding | Enterprise policies under Microsoft 365 governance | Azure Grounding with Bing tool (enterprise) | Web (Bing/Edge), Microsoft 365 integration | Free (consumer); enterprise via M365 | Everyday users; Microsoft 365 organizations |
| Phind (Query Search) | Meta over docs/web | Answer + code focus; cites sources | Live web (documentation limited) | Pro plans offer model options | Privacy policy available | No official public REST API documentation; some unofficial wrappers exist | Web; community VSCode extension | Free; Phind Pro $15/mo | Developers seeking technical Q&A and code examples |
| Google AI Overviews | Google's own index (first-party) | Snapshot answer + linked sources at top of SERP | Appears on many queries; global rollout | Gemini-based (Google-managed) | Google Search privacy policies | None (user-facing only) | Google Search (web, mobile) | Free | Consumers; everyday search for quick context |
| You.com | Hybrid/meta; customizable Apps and Skills | Chat answers with source tiles | N/A | Optional zero-retention model routing for some Anthropic endpoints | Privacy policy; certain third-party LLMs offer zero-retention | API & SDKs available | Web, Chrome/Edge extensions, mobile | Free; Pro $9.99/mo; API usage-based | Power users wanting customization and privacy control |
| Consensus | ~200M scholarly papers/chapters (academic corpus, not general web) | Evidence-based summaries with paper citations | Academic corpus (not general web; not real-time news) | LLM used after retrieval (details not public) | Privacy policy; educational deployments | None | Web; library integrations | Free; Pro $8.99/mo | Scholars, students, analysts conducting literature reviews |
| Brave Search | Own independent index | Link list + optional AI Answers with references to source pages | Web index continuously updated; AI Answers include references for key claims | N/A (proprietary summarization) | No tracking per privacy notice; no ads | Search API (free tier; paid $3-$9 per 1K requests) | Web, Brave browser integration | Free; Premium $3/mo; API usage-based | Privacy-focused users wanting independent, ad-free search |
| Andi | Meta-aggregation | Chat-style answer + sources | Claims live data (specifics limited) | N/A | Ad-free, tracking-free per Privacy Promise | Dev API page exists but public docs are limited | Web/PWA | Free; Dev API pricing N/A | Consumers wanting simple, clean, private answers |
| Kagi | Own/curated index + meta | Link list; optional Summaries; heavy user controls via Lenses | Fresh web results; user tuning (boosts/blocks with Lenses) | N/A (proprietary) | Strict privacy per policy; no ads; no tracking | Limited (user-facing focus) | Web, browser/search integration | Paid only: $5-25/mo tiers | Power users and researchers wanting precise control, no ads |
| Exa | Crawls live web; dev-focused | Returns URLs/snippets for your LLM (no UI answer) | Real-time search/crawl | N/A (you bring your own model) | Privacy policy | REST API (search/crawl/extract endpoints); SDKs | API only (no consumer UI) | Usage-based API pricing (see website) | Developers building agents or platforms needing programmatic search |
All official sources (privacy policies, API docs, pricing pages) are linked in the tool names with UTM tracking for attribution.
Based on the comparison and evaluation, here are the best AI search engines for specific scenarios and roles.
Perplexity delivers the best balance of citation quality, freshness, and usability. Its real-time crawling, documented user-agent policies, and SOC 2 compliance make it suitable for professional research. Pro plans offer model selection (GPT-4, Claude, etc.) and Spaces for organizing research threads by project. Free tier provides generous access for casual users.
When to choose: You need fast, verifiable answers with transparent sources for research, journalism, or everyday questions.
Completely free with no query limits, Copilot shows synthesized answers with an expandable source list. Freshness controls (Day/Week/Month) via Bing grounding let you prioritize recent sources—users can expand the source list and verify timestamps on each cited article. Native integration with Edge and Microsoft 365 adds convenience for existing Microsoft users.
When to choose: You want full-featured AI search at no cost, or you're already in the Microsoft ecosystem.
Phind (Query Search) + Exa API
Phind specializes in coding and technical documentation with cited sources, making it ideal for developer Q&A. For programmatic integration, Exa provides clean REST endpoints (search/crawl/extract) to ground your own LLM in agent pipelines.
When to choose: You're a developer seeking quick access to docs and examples (Phind) or building an AI application that needs programmatic search (Exa).
With a corpus of ~200M scholarly papers and chapters from the academic literature, Consensus synthesizes findings from peer-reviewed sources and provides direct paper citations you can export. The Consensus Meter visualizes agreement/disagreement across studies, and Pro Analysis offers deeper insights.
When to choose: You're conducting literature reviews, need explainable academic citations, or want synthesis across scholarly sources.
Kagi (paid) or Brave Search (free)
Both maintain independent indexes and commit to no user tracking. Kagi offers unmatched control with Lenses (pre-filter sources) and per-site boosts/blocks, but requires a paid subscription. Brave provides ad-free, privacy-first search with optional AI Answers for free.
When to choose: Privacy is non-negotiable, you're researching sensitive topics, or you want to avoid ad-funded models.
Deeply integrated with Bing, Edge, and Microsoft 365, Copilot Search inherits enterprise policies, audit logs, and compliance frameworks. For organizations already using M365, it offers zero-friction deployment and governance.
When to choose: Your organization uses Microsoft 365, and you need governed, compliant AI search within existing IT policies.
Built directly into Google Search, AI Overviews appear automatically for eligible queries, showing synthesized snapshots with linked sources. No setup, no signup—just search as usual and get AI-enhanced results when helpful.
When to choose: You use Google Search daily and want quick orientation without switching tools. (Always verify claims by checking the linked sources.)
Perplexity's live crawling and transparent link cards make it ideal for breaking news and current events. Documented crawler user-agents and real-time fetch capabilities ensure fresh coverage with visible publication dates. Note: Verify robots.txt compliance for sensitive sites.
When to choose: You're a journalist, analyst, or anyone who needs up-to-the-minute information with verifiable sourcing.
Purpose-built for developers, Exa offers search, crawl, and extract endpoints with SDKs and clear documentation. Pay-as-you-go pricing and rate limits per plan make cost predictable. Use Exa to ground your LLM with fresh web data.
When to choose: You're building an AI application, agent, or platform that needs programmatic web search and retrieval.
Kagi's Lenses and per-site ranking controls give unmatched customization. Boost trusted sources, block low-quality sites, create custom views (e.g., "only academic papers" or "only official docs"), and search without ads or tracking.
When to choose: You're a power user or researcher who wants precise control over source quality and ranking, and you're willing to pay for it.
Quick Decision Guide:
Start with the free tier of your top pick, test with real queries, and upgrade when you need advanced features like model selection, custom Lenses, or API access.
Integrating AI search engines into your daily workflows improves research speed, verification quality, and knowledge retention. Here's how to use AI search effectively across common use cases.
Step 1: Start with a scoped question
Step 2: Review the answer and open key citations
Step 3: Ask follow-up questions
Step 4: Save and organize
Step 5: Verify before citing
Tools: Perplexity (general research), Consensus (academic), Bing Copilot (everyday)
Step 1: Ask for code + docs
Step 2: Verify the example
Step 3: Request alternatives
Step 4: Integrate into your workflow
Tools: Phind (UI), Exa (API for automation)
Step 1: Set freshness filters
Step 2: Cross-check publication dates
Step 3: Follow developing stories
Step 4: Cite responsibly
Tools: Perplexity (real-time crawling), Bing Copilot (freshness controls)
Step 1: Choose a no-tracking engine
Step 2: Use domain restrictions
site:gov or site:*.edu for trusted sourcesStep 3: Verify privacy claims
Step 4: Clear state after sensitive queries
Tools: Kagi, Brave, Andi, You.com (zero-retention models)
Step 1: Use a paper-focused engine
Step 2: Review the Consensus Meter
Step 3: Export citations
Step 4: Supplement with general search
Step 5: Cite original sources
Tools: Consensus (primary), Perplexity (supplementary), Google Scholar (exhaustive)
Step 1: Choose an API-first engine
Step 2: Set up in a staging environment
Step 3: Ground your LLM
Step 4: Cache and dedupe
Step 5: Monitor and optimize
Tools: Exa (best dev experience), Perplexity Search API, Brave API
By integrating these workflows, you leverage AI search engines as research accelerators while maintaining verification rigor and source attribution standards.
AI search engines are evolving rapidly as language models improve, indexing becomes more real-time, and user expectations shift toward verifiable, conversational answers. Here are the key trends shaping the next 3-5 years.
Current state: Leading engines (Perplexity, Bing Copilot) provide inline citations, but users must manually verify claims by opening links.
3-5 year outlook:
Why it matters: As AI-generated content floods the web, distinguishing authoritative sources from synthetic or low-quality content becomes critical. Trustworthy search depends on transparent, auditable sourcing.
Current state: Text-based retrieval dominates; real-time crawling exists (Perplexity, Exa) but is limited to web pages.
3-5 year outlook:
Why it matters: Knowledge isn't just text on web pages. As AI models become multimodal (GPT-4 Vision, Gemini, Claude 3), search engines will follow, enabling richer, cross-media research.
Current state: Privacy-focused engines (Kagi, Brave, Andi) exist but remain niche; mainstream options (Google, Bing) rely on user data.
3-5 year outlook:
Why it matters: Privacy concerns are rising, especially for sensitive research (health, legal, political). Demand for no-tracking, user-controlled search will grow, particularly in Europe and among professionals.
Current state: APIs exist (Exa, Perplexity, Brave) but are used primarily by developers building custom apps.
3-5 year outlook:
Why it matters: As AI agents proliferate (coding copilots, personal assistants, enterprise bots), search becomes an API service rather than a user-facing product. Developers will choose engines based on latency, cost, and citation quality.
Current state: Tension between AI search engines and publishers over traffic, attribution, and copyright. EU antitrust complaints filed against Google AI Overviews; some publishers block AI crawlers.
3-5 year outlook:
Why it matters: If publishers block AI crawlers, search quality degrades. Sustainable models that compensate creators while enabling AI synthesis are critical for the ecosystem's health.
Current state: Generalist engines dominate; niche tools (Consensus for academic, Phind for code) serve specific verticals.
3-5 year outlook:
Why it matters: General-purpose search can't match the depth, compliance, and trust requirements of specialized domains. Vertical-specific AI search engines will emerge, often behind paywalls or enterprise licenses.
Current state: Limited customization (Kagi Lenses, Brave Goggles) available; most engines offer one-size-fits-all results.
3-5 year outlook:
Why it matters: One-size-fits-all rankings don't serve specialized needs. Power users and professionals will demand control over source selection, model choice, and ranking logic.
AI search engines will mature from experimental tools to essential infrastructure, provided they solve the trust, transparency, and sustainability challenges currently in flux.
What's the main difference between AI search and traditional search?
AI search writes a synthesized answer with citations; traditional search returns a ranked list of links. Use AI search for quick understanding and starting hypotheses, then validate by opening the cited sources. Switch to traditional search for exhaustive discovery, niche sites, or when you need precise operator control (e.g., site:, filetype:). (Microsoft Copilot Search)
How do I ensure fresh results for news or fast-changing topics?
Use engines with freshness controls. In Bing Copilot Search, set grounding parameters to Day/Week/Month to prioritize recent sources. In Perplexity or other engines, add time constraints in your query (e.g., "in the past week"). Always open cited links and check publication dates to verify recency. (Microsoft Learn - Bing Grounding)
How can I constrain which sites an AI answer uses?
Add site: operators in your query (e.g., "climate change site:gov OR site:*.edu") to limit sources to trusted domains. Some engines offer built-in controls: Kagi's Lenses let you create custom source filters, and Brave's Goggles allow community-defined ranking rules. Use these features to boost authoritative sources and exclude low-quality sites. (Kagi Lenses)
What's the safest way to verify claims in AI-generated answers?
Require cited sources, open at least 2-3 independent links, and cross-check that claims match the source content. For critical facts, ask the AI to provide direct quotes with links, then navigate to the exact passage in the original source. Never rely solely on the AI's summary—always verify in the primary sources.
How do I use AI search for academic work without plagiarism?
Use AI search engines (especially Consensus for literature) to find and understand papers, but always cite the original paper you read, not the AI-generated summary. Avoid copying AI-generated text directly. Treat AI search like a research assistant that points you to sources, then do your own reading and paraphrasing. (University of St. Thomas - Consensus)
What are tips for developer queries and technical documentation search?
Ask for exact code snippets plus links to official docs (e.g., "Show Python code for OAuth2 with links to docs"). Request "sources that disagree" to surface alternative approaches. Use Phind for interactive technical Q&A. If building agents, ground your LLM with Exa API results to programmatically retrieve and cite documentation. (Exa)
What about privacy and data retention in AI search engines?
Privacy varies widely. For maximum privacy, use engines with no-tracking commitments (Kagi, Brave, Andi). For enterprise needs, check for SOC 2 compliance and clear retention policies (Perplexity Enterprise). You.com offers zero-retention model options via Anthropic. Always read the privacy policy; for sensitive research, sign out or use guest modes. (Perplexity Privacy & Security)
How do API usage and cost control work for AI search?
Start with Exa or Perplexity Search API in a staging environment. Log query volume and set spending caps. Pricing is typically pay-as-you-go (per query or per 1K requests). Cache stable results (e.g., "What is X?" definitions) and deduplicate queries to reduce costs. Check official API docs for current pricing and rate limits. (Exa)
How do I handle paywalls when AI search cites paywalled articles?
Favor engines that link out so you can use institutional or library access for papers. Many universities provide access to journals via proxies. Do not bypass paywalls or violate publisher terms. If you can't access a paywalled source, ask the AI to find open-access alternatives or pre-prints (e.g., arXiv for academic papers).
Are Google AI Overviews reliable?
Google AI Overviews provide quick context and are improving, but they've faced scrutiny for occasional inaccuracies and impact on publisher traffic. They cannot be fully disabled—use standard results view when precision matters. Always verify claims by checking the linked sources. For critical research, consider dedicated AI search engines with stronger citation practices (Perplexity, Bing Copilot). (Wired - AI Overviews)
What should enterprises consider for deployment and compliance?
For Microsoft 365 organizations, use Bing Copilot Search with Bing grounding inside governed environments; verify data retention and compliance via tenant policies. For other providers, check for SOC 2 reports, GDPR compliance, and audit logs (Perplexity Enterprise offers these). Ensure the engine's privacy policy aligns with your data governance requirements. (Microsoft Learn)
Can I trust AI search for medical or legal advice?
No. AI search engines are research tools, not substitutes for professional advice. For medical or legal questions, use AI search to find sources and understand topics, but always consult qualified professionals. Verify information from authoritative sources (e.g., .gov, peer-reviewed journals) and disclose to professionals that you used AI-assisted research.
Which AI search engine is best for privacy-sensitive research?
Kagi (paid, no tracking, strict privacy policy) and Brave Search (free, independent index, no tracking) are top choices. Andi also commits to no ads or tracking. For zero-retention model options, try You.com with Anthropic models. Avoid ad-funded engines for sensitive topics. (Brave Search Privacy)
How do I compare multiple AI search engines efficiently?
Run the same query on 2-3 engines (e.g., Perplexity, Bing Copilot, Google AI Overviews), then compare:
Choose the engine that consistently delivers the best citations and freshness for your queries.
What happens if a tool I rely on changes pricing or features?
AI search is evolving rapidly. Bookmark official pricing and changelog pages. For critical workflows, test 2-3 alternatives so you have fallback options. If using APIs, abstract your integration (use a wrapper function) to make switching easier. Monitor community discussions (Reddit, Twitter) for early warnings about changes.