Best AI Answer-Engine APIs
Search APIs that return a generated answer with citations rather than only a list of links.
Our pick: Exa
Exa is a REST API for web search, content crawling, and research agents, designed specifically as a grounding and retrieval layer for LLM applications and AI agents. It offers neural search, full-page content extraction, news and research paper search, scheduled monitors, and an answer-with-citations endpoint, with SDKs for Python, JavaScript, and an MCP server. Pricing is usage-based at $1.00 per 1,000 requests, with a free tier of 20,000 requests per month and self-serve signup; an enterprise plan is available. The service holds SOC 2 Type 2 and HIPAA certifications, and customers include Cursor, Notion AI, HubSpot, and Databricks.
Best for: Prototypes and side projects - free to start, no sales call; Regulated or enterprise workloads - compliance attestations and an enterprise plan; AI agents and automation - an agent-ready surface (MCP / llms.txt).
Best for…
Ranked (7)
#1 Exa
74 / 100- Best overall
- Only free option
- Best for enterprise
- Cheapest to start
- Best for agents
Exa is a REST API for web search, content crawling, and research agents, designed specifically as a grounding and retrieval layer for LLM applications and AI agents. It offers neural search, full-page content extraction, news and research paper search, scheduled monitors, and an answer-with-citations endpoint, with SDKs for Python, JavaScript, and an MCP server. Pricing is usage-based at $1.00 per 1,000 requests, with a free tier of 20,000 requests per month and self-serve signup; an enterprise plan is available. The service holds SOC 2 Type 2 and HIPAA certifications, and customers include Cursor, Notion AI, HubSpot, and Databricks.
PricingUsage · from $1 1,000 requests · free tier ✓TrustSOC 2 Type II · HIPAADoesUsed byCursor, Cognition, HubSpot, OpenRouter#2 Brave Search API
59 / 100Brave Search API gives developers access to Brave's independent web index of over 30 billion pages for building AI products, RAG pipelines, chatbots, and search engines, with endpoints covering web, news, image, video, local place search, answers, and LLM context. Pricing is usage-based at $4 per 1,000 requests, with a free tier of roughly $5 in monthly credits, self-serve signup, and an enterprise plan available. The API is SOC 2 Type 2 certified and GDPR compliant, ships with an MCP server, and counts Cohere, Mistral AI, AWS, Shopify, and Snowflake among its documented customers. Usage terms prohibit storing results or using them to train AI models, and attribution is required in customer applications.
PricingUsage · from $4 1,000 requests · free tier ✗TrustSOC 2 Type II · GDPRDoesUsed byApollo, AWS, Axel Springer, CheggThe catchAn independent index rather than a Google/Bing reseller, at a low per-query price, but results may not be stored, cached, or used to build a database.#3 Jina AI Search Foundation (DeepSearch / Reader)
58 / 100- Broadest surface
Jina AI Search Foundation is a suite of LLM-oriented search and retrieval APIs covering URL-to-Markdown conversion, web search, iterative deep research, fact-checking, multilingual embeddings, reranking, and text segmentation, aimed at developers building RAG pipelines, AI agents, and answer engines. Pricing is usage-based at $0.05 per million tokens, with a 10 million token free tier shared across all APIs and no sales call required to get started. EU-dedicated endpoints are available for data-residency needs, the platform is GDPR-compliant, and a remote MCP server is supported alongside JavaScript and Node.js SDKs. API inputs and outputs are not used to train Jina's models.
PricingUsage · from $0.05 1,000,000 tokens · free tier ✗TrustGDPRDoesUsed bySingapore Airlines, Salesforce, Alibaba, AWSAvoid ifYou want to try it free before paying#4 Parallel Search API
61 / 100Parallel Search API is a REST-based web search and extraction service built for AI workloads, covering RAG grounding, agent pipelines, deep research, entity discovery, and web monitoring. Pricing is usage-based at $4.00 per 1,000 requests, with a free tier of 20,000 requests and an enterprise plan available; signup is self-serve. The API ships SDKs for Python, TypeScript/JavaScript, and LangChain, and offers an MCP server alongside webhooks. It holds SOC 2 Type 2 certification and contractually commits to not training on customer data, with zero data retention available under enterprise agreements.
PricingUsage · from $4 1,000 requests · free tier ✗TrustSOC 2 Type IIDoesUsed byClay, Sourcegraph, Harvey, NotionAvoid ifYou want to try it free before paying#5 You.com Search API
72 / 100You.com Search API provides real-time web search, news retrieval, and AI-grounded research capabilities designed for RAG pipelines, LLM agents, and agentic applications. Pricing starts at $5 per 1,000 searches on a usage-based model, with $100 in complimentary credits on signup and a free unauthenticated tier of 100 queries per day. The REST API supports Python and TypeScript SDKs, an MCP server, and both API key and OAuth2 authentication, and is SOC 2 Type 2 certified with GDPR compliance. Customers include Amazon, Databricks, DuckDuckGo, Bank of America, Harvey, and Windsurf.
PricingUsage · from $5 1,000 searches · free tier ✗TrustSOC 2 Type II · GDPRDoesUsed byDuckDuckGo, Harvey, Windsurf, DatabricksAvoid ifYou want to try it free before paying#6 Kagi Search API
53 / 100Kagi Search API provides programmable access to Kagi's premium search index, covering web, image, news, video, podcast, and content extraction endpoints, with built-in summarization and citation-grounded answers suited for RAG pipelines and AI agents. Pricing is usage-based at $12 per 1,000 searches with no sales call required, and an enterprise plan is available. The API is GDPR compliant, supports Python, Go, Rust, and TypeScript SDKs, and ships an MCP server for agent tooling integrations.
PricingUsage · from $12 1,000 searches · free tier ✗TrustGDPRDoesAvoid ifYou want to try it free before paying#7 Perplexity Sonar API
73 / 100Perplexity Sonar API is a REST-based search and language model service that lets developers add real-time web retrieval, Q&A with inline citations, deep research, and semantic embeddings to their products. Pricing is usage-based starting at $1.00 per million tokens, with self-serve signup and no sales call required. The API ships SDKs for Python, TypeScript, and Node.js MCP, holds SOC 2 Type 2 certification, enforces a zero data-retention policy, and counts Samsung among its documented customers.
PricingUsage · from $1 1M tokens · free tier ✗TrustSOC 2 Type IIDoesUsed bySamsungThe catchAn LLM answer engine priced per token, not a raw results API; ideal for cited answers, the wrong tool if you need ranked links to rank-track or scrape.