Exa

Exa is a semantic search API built on its own 500B+ page index, with page text included in search results, strong entity-lookup accuracy, an official MCP server, and per-request pricing from $4/1k. It is not a benchmark leader across the board—it is statistically tied with Brave and Firecrawl on independent agentic search benchmarks—and its 10 QPS limit, non-paginating search, crawl-bounded recency, and Enterprise-only compliance features are hard constraints that require workflow design around them.

semantic search APIneural searchAI agent searchweb indexpage contentsMCP serverRAG retrievalentity lookuppay-as-you-goDeep Search
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Overview

What is Exa?

Exa is a search API for AI agents, not a search engine for people. It was founded in 2021 as Metaphor and renamed Exa in 2024. The company builds its own web index—more than 500 billion pages—and runs semantic search over it, matching on what a query means rather than on exact keywords. The official positioning is that Exa is “built for software rather than people”: given a query, it returns ranked results with extracted text and highlights, so the agent does not need to fetch and parse each page separately.

The architecture is the product's identity. Most search APIs return links; the caller then has to crawl the page, strip boilerplate, and extract the text the model needs. Exa returns the text inline for up to 10 results, and it exposes a separate Contents endpoint for pulling text from URLs the agent already holds. That pipeline—find and read in one layer—is why Exa is used in production by Cursor, Cognition, and HubSpot, and why it has an official hosted MCP server and more than 50 framework integrations[reference:12].

The product surface has six endpoints. Search runs in several modes: Lite (cached content, lowest cost), Instant and Fast (legacy speed tiers), Auto (the default, which selects the best method per query), and Deep Search (deep-lite, deep, deep-reasoning) for multi-step research with structured outputs. Contents extracts text, highlights, or summaries from known URLs. Answer synthesizes a cited response in one call. Monitors run scheduled searches and push new events via webhook. The Agent API runs asynchronous deep research, list-building, and enrichment with fixed-effort pricing from $0.012 to $1.00 per run or metered usage against Agent Compute Units. Websets, the list-building interface, has its own concurrency limits.

Pricing is pay-as-you-go with a free tier that resets monthly. The $10 monthly credit is not a request allowance—it is a dollar balance spent at standard rates. Lite search is $4 per 1k requests, Auto and Fast are $7, Deep Search is $12–15, Contents is $1 per 1k pages, Answer is $5, and Monitors is $15. Up to 10 results are included per search; each additional result is $1 per 1k. Page summaries are $1 per 1k pages. The free credits do not accumulate: unused balance expires at the end of each month, so the balance never exceeds $10. A one-time $10 onboarding bonus is available for the first team and does not expire.

The constraints that do not show up in the pricing table are rate limits, pagination, and index boundaries. Search and Answer are capped at 10 QPS per team; Deep Search at 5 QPS; Contents at 100 QPS; Agent at 5 QPS with 50 concurrent runs. The 25 QPS upgrade requires purchasing $1,000 in credits within a 30-day window, not spending it, and lasts 90 days. Search does not paginate—numResults goes up to 100 and stops. The index is the boundary for recency: a page published minutes ago may not be crawled yet, and direct factual lookups can return semantically-similar-but-wrong matches when the target is missing. These are not defects in the sense of bugs to be fixed; they are properties of an index-based semantic search architecture, and they define the workloads where Exa fits and where it does not.

Workflow

How does Exa work?

A developer sends a POST request to api.exa.ai/search with a natural-language query. The required parameter is query; optional parameters include type (lite, instant, fast, auto, deep-lite, deep, deep-reasoning), numResults (1–100, default 10), contents (highlights, text, summary), category (company, people, news, publication, personal site, financial report), includeDomains and excludeDomains, and startPublishedDate and endPublishedDate. The API returns ranked results, each with an id, title, URL, publication date when known, and the requested content. When outputSchema is supplied, Exa synthesizes a text or JSON answer on top of the ranked pages, returned in output.content with field-level sources and confidence in output.grounding.

The type parameter is the main lever for latency and cost. Lite serves cached content only and rejects maxAgeHours. Instant and Fast are legacy speed tiers. Auto is the default and selects the best method per query. Deep-lite, deep, and deep-reasoning run multi-step retrieval and synthesis, with latencies from about 4 seconds to 40 seconds and prices from $12 to $15 per 1k requests[reference:14]. The Contents endpoint takes a list of URLs and returns text, highlights, or summaries at $1 per 1k pages per content type. Answer takes a question and returns a cited response at $5 per 1k requests. Agent takes a task and an effort level, runs asynchronously, and returns structured output; the fixed-effort prices are $0.012 (minimal), $0.025 (low), $0.10 (medium), $0.50 (high), and $1.00 (xhigh), with metered auto capped at $5 per run and metered ultra capped at $20[reference:15].

The MCP server is the integration path for agent clients. It is hosted, requires no API key for limited use, and exposes search, contents, and answer as tools. The Python and JavaScript SDKs wrap the REST API, and integrations exist for OpenAI, Vercel AI SDK, LangChain, CrewAI, LlamaIndex, Pydantic AI, n8n, and MCP clients. The OpenAPI spec is published, and the full documentation is available as llms.txt and llms-full.txt for agent consumption[reference:16].

Use cases

Use Cases

  • Semantic discovery where the query is a description, not a keyword: “startups building humanoid robots in Europe,” “papers arguing against scaling laws,” “companies that recently raised a Series B in climate tech”
  • Entity lookup: finding the right person, company, or academic paper when name matching is unreliable and keyword search returns noise
  • Feeding RAG pipelines and agents with page text in the same call as the search, eliminating a separate scraping step for up to 10 results
  • Deep Search for multi-step research that needs structured output and citations, at $12–15 per 1k requests
  • Single-call cited answers through the Answer endpoint, for applications that need a synthesized response with sources rather than a list of links
  • Scheduled monitoring of a topic or set of pages, with webhook delivery of new events
  • Asynchronous list-building and enrichment through the Agent API, with fixed-effort pricing for predictable per-run costs
Pricing

Pricing

Pricing model: Freemium

Plan Price Billing Included usage Notes
Free $0 per month $10 in credits every month, plus a one-time $10 onboarding bonus for the first team. Credits reset on the 1st of each calendar month and do not accumulate—unused credits never carry over, so the balance never exceeds $10 at a time. Up to 2,500 Lite searches per month. 10 QPS on Search and Answer, 5 QPS on Deep Search, 100 QPS on Contents, 50 concurrent Agent runs. No payment method required. Access to every endpoint. Free credits are spent at standard pay-as-you-go rates. —
Pay as you go Usage-based no subscription Prepaid credits with no subscription and no minimum spend. 10 QPS baseline; rises to 25 QPS automatically for 90 days after purchasing $1,000 in credits within a 30-day window. Auto-recharge configurable from $5 to $10,000 per trigger, with an optional monthly cap. Rate: $4 per 1k Lite or Instant searches, $7 per 1k Auto or Fast searches, $12–15 per 1k Deep Search requests, $1 per 1k Contents pages, $5 per 1k Answer requests, $15 per 1k Monitors requests, Agent from $0.012 to $1.00 per fixed-effort run or usage-based. —
Enterprise Custom annual Custom volume pricing, optional postpaid invoicing, custom rate limits beyond 25 QPS, SLAs, Zero Data Retention, HIPAA, SSO, and custom indexes. Contact sales. —
Free tier: The Free tier is $10 in credits per month, not a fixed request count. At the Lite rate of $4 per 1k searches, that is nominally 2,500 searches, but the effective count drops with every add-on: Auto or Fast search is $7 per 1k (about 1,428 searches), page summaries add $1 per 1k pages, and Deep Search is $12–15 per 1k (about 666–833 searches). The grant resets on the 1st of each month and does not roll over. A one-time $10 onboarding bonus is available to the first team and does not expire. No credit card is required. When credits are exhausted, requests return HTTP 402 until the next monthly reset or a manual top-up.
Limitations

Common Limitations

  • 10 QPS on Search is a hard ceiling for concurrent agent workloads · Exa's default rate limit is 10 queries per second on /search and /answer, and 5 QPS on Deep Search. This limit applies to the team as a whole across all API keys, so adding keys does not raise it. The upgrade to 25 QPS is automatic only after purchasing $1,000 in credits within a 30-day window—spending $1,000 does not qualify, only buying it does—and the increase lasts 90 days before requalification. For a single agent making sequential calls, 10 QPS is ample. For a fleet of agents running in parallel, or for a batch enrichment job, it is a burst bottleneck that produces HTTP 429 responses and requires exponential backoff on the client side. A published GAIA validation campaign recorded 1,341 HTTP 429 errors from Exa, accounting for 44% of all tool failures in that run—the single largest source of failure by a wide margin[reference:0]. That is not a benchmark of Exa's search quality; it is a benchmark of what happens when an agent fleet meets a 10 QPS limit without adequate retry logic.
  • Statistical parity with competitors, not dominance, on agent search benchmarks · Exa's own marketing emphasizes semantic accuracy, and on entity-lookup benchmarks it does outperform Tavily and Firecrawl substantially—75.5% top-result precision on people profiles versus 40.5% and 41.6%, and 81.5% on company lookups versus 61.3% and 61.7%[reference:1]. But those benchmarks are run by Exa. On the independent AIMultiple agentic search benchmark of 100 AI/LLM queries across eight APIs, Exa scored 14.39, statistically indistinguishable from Brave (14.89), Firecrawl (14.58), and Parallel Search Pro (14.21) because the confidence intervals overlap[reference:2]. In the Artificial Analysis Search Index for October 2026, Exa auto scored 74, one point behind Parallel Search advanced (75) and six behind Perplexity Search (80)[reference:3]. The honest read is that Exa is a strong default for semantic and entity search, not a universal leader across every query type and every benchmark. Teams that need the absolute highest score on a specific benchmark should run their own evaluation rather than assuming Exa's entity-lookup advantage generalizes.
  • The index is the boundary: recency is bounded by crawl cadence · Exa runs semantic search over its own index, built from a crawl of more than 500 billion webpages. That architecture is the source of its accuracy on entity lookups and its ability to return page text in the same response. It is also the source of its hardest limitation: recency is bounded by crawl cadence, not by live retrieval. A page published minutes ago may not be in the index. Independent analysis notes that “very direct factual lookups can return semantically-similar-but-wrong matches” when the index does not contain the exact target[reference:4]. Exa's own alternatives guide concedes that competitor comparisons sometimes point to “index freshness for brand-new content” as a drawback[reference:5]. For workflows that require the most recent version of a page, or that need to read a specific URL's live content, Exa's Contents endpoint returns what the crawler last captured—not a fresh fetch. Firecrawl renders JavaScript on a live fetch; Exa returns the cached snapshot. The two are often used together for exactly this reason: Exa finds the pages, Firecrawl fetches them live when freshness matters.
  • Search does not paginate, and category filters have documented gaps · Exa's search endpoint does not support pagination. numResults accepts 1 to 100 with a default of 10, and the API returns that many results and stops. There is no cursor or offset for retrieving the next page. For an agent that needs to exhaustively enumerate results—competitive research, list building, due diligence across many sources—the only option is to issue multiple queries with different phrasings and deduplicate client-side. Separately, the company and people categories do not support startPublishedDate, endPublishedDate, or excludeDomains filters; using them returns HTTP 400. The lite search type serves cached content only and rejects contents.maxAgeHours with any value, including -1[reference:7]. These are documented spec constraints, not bugs, but they are not surfaced prominently during evaluation, and they force workflow redesign when discovered in production.
  • Latency variance makes sub-second guarantees unreliable · Exa's median latency in vendor-run benchmarks is attractive—472 ms in one comparison run, against 1.3 s for Perplexity Sonar and 3.6 s for Tavily[reference:8]. But independent latency measurements show substantial variance: Auto latency on non-news queries was 1.96 s p50 on October 13 and 6.6 s on October 14, with server time pinned at almost exactly 6.05 s on every query in the second measurement[reference:9]. That pattern—a bimodal distribution with a long tail—means an agent designed around a 500 ms budget will occasionally see 6-second responses. For real-time applications such as customer-facing assistants or autocomplete, the variance is more consequential than the median. The Content endpoint is faster (100 QPS) and returns cached text in milliseconds when the page is stored, but search itself is not a low-latency guarantee under load.
  • No end-user app, and compliance features are Enterprise-only · Exa is developer infrastructure. There is no end-user research interface, no dashboard for non-technical users, and no built-in UI beyond the billing and API key management pages. Zero Data Retention, HIPAA, and SSO are reserved for Enterprise plans; Free and pay-as-you-go users do not have these controls[reference:10]. For teams evaluating Exa as part of a regulated workflow, this means the self-serve tier cannot be used as a stopgap while the Enterprise contract is negotiated—the compliance features simply are not present. The review trail on major software review sites is also thin: one G2 review as of independent verification, so the evidence base rests more on named customers (Cursor, Cognition, HubSpot) and vendor-published benchmarks than on aggregated user reviews[reference:11].
Features

Key Features

  • Semantic search over Exa's own index of 500B+ webpages
  • Page text and query-relevant highlights included in search results (up to 10 results)
  • Multiple search types: Lite, Instant, Fast, Auto, and Deep Search (deep-lite, deep, deep-reasoning)
  • Contents endpoint for extracting text, highlights, or summaries from known URLs at $1 per 1k pages
  • Answer endpoint for single-call cited responses at $5 per 1k requests
Comparison

Exa vs. Tavily and Brave Search API

This comparison uses official pricing pages, documentation, and independently published benchmark data available as of November 2026. It focuses on the structural differences that determine retrieval accuracy, throughput ceiling, and cost structure—not on declaring a universal winner. Exa is a semantic search API over its own index; Tavily is an AI-agent search API with a free credit model and a thinner public disclosure of its retrieval stack; Brave Search API is an independent index built for high-throughput, keyword-oriented retrieval. The three overlap at the search endpoint but diverge on what they index, how they price content, and how fast they let you go.

Tool Positioning Key differences Best fit Pricing note
Exa Official pricing Billing and rate limits Independent benchmark (AIMultiple agentic search, statistical parity) A semantic search API built on its own 500B+ page index, differentiated by entity-lookup accuracy, page text included in search results, and a full suite of retrieval endpoints (Search, Contents, Answer, Deep Search, Monitors, Agent). The only API in this comparison that runs semantic search over its own index and returns page text with each result. Strongest documented entity-lookup accuracy (75.5% on people profiles, 81.5% on company lookups in vendor benchmarks). But 10 QPS on Search is a hard ceiling for agent fleets, the 25 QPS upgrade requires purchasing $1,000 in credits, search does not paginate, and the index bounds recency. On independent agentic search benchmarks, Exa is statistically tied with Brave and Firecrawl rather than ahead. Contents is a separate meter at $1/1k pages, so 'content included' applies to search results, not to URL extraction. Agents and RAG pipelines that need semantic discovery, entity lookup, or page text in the search response, and that can live within a 10 QPS limit or purchase the 25 QPS upgrade. Free: $10 credits/month (≈2,500 Lite searches), resets monthly, no rollover, no card. Pay-as-you-go: $4/1k Lite or Instant, $7/1k Auto or Fast, $12–15/1k Deep Search, $1/1k Contents pages, $5/1k Answer, $15/1k Monitors, Agent $0.012–$1.00/run. Enterprise custom with ZDR, HIPAA, SSO.
Tavily Tavily vs Exa comparison (independent, documents precision and latency gaps) Exa alternatives guide (Tavily credit pricing and free tier) A web access API for AI agents, with search, extract, map, crawl, and multi-step research endpoints, a free plan of 1,000 credits per month, and pricing at $0.008 per credit pay-as-you-go. Tavily's free tier is denominated in credits (1,000 per month) rather than dollars, and its pay-as-you-go rate is $0.008 per credit, falling to $0.005–$0.0075 on committed plans. It offers search, extract, map, crawl, and research endpoints, and an official MCP server. Its documentation does not disclose a proprietary index or a semantic search mode; it returns model-ready snippets rather than full page text. On the vendor-run entity benchmark, Tavily scored 40.5% on people profiles and 61.3% on company lookups, against Exa's 75.5% and 81.5%. Median latency in that benchmark run was 3.6 s for Tavily versus 472 ms for Exa. Tavily's research requests bill at 4–250 credits each, and production keys at 1,000 requests per minute require a paid plan. Its terms permit training on inputs and outputs unless ZDR is enabled per account. Prototypes and early agent projects where a free credit allowance, broad endpoint coverage, and quick setup matter more than retrieval precision or low latency—and where per-account ZDR can be enabled if data handling is a concern. Free: 1,000 credits/month, no card required. Pay-as-you-go: $0.008/credit, falling to $0.0075 and $0.005 on committed plans from $30 to $500/month. Research requests 4–250 credits each. Production rate of 1,000 requests/minute requires a paid plan.
Brave Search API Independent benchmark (AIMultiple, Brave top score with overlapping CIs) Independent API comparison (documents 50 QPS free tier and keyword mode) An independent search index with a high-throughput API, built for keyword-oriented retrieval and raw request volume rather than semantic understanding or inline page content. Brave runs its own independent index—one of the few alternatives to Google or Bing—and offers the highest throughput among the three on the free tier: 50 requests per second, with $5 in monthly credit (about 1,000 requests) and a card required for abuse checks. On the independent AIMultiple agentic search benchmark, Brave scored 14.89, slightly ahead of Exa (14.39) and Tavily (13.67), though the difference is not statistically significant. Brave's documented mode is keyword matching, not semantic search, and it returns links rather than page text—the caller fetches and parses the pages. It does not offer a single-call cited answer comparable to Exa's Answer endpoint. Brave is the throughput choice; Exa is the semantic and entity-lookup choice. High-volume keyword search where throughput and raw request speed matter more than semantic understanding or inline page content, and where the caller is prepared to fetch and parse result pages separately. Free: $5 monthly credit (≈1,000 requests), 50 QPS, card required. Paid plans scale by request volume; check the official page for current rates. No per-page content in results; fetching is separate.

Comparison checked against official product information on 2026-11-04. Features and pricing may change.

FAQ

Frequently Asked Questions

Is Exa free to use?

Exa has a free tier with $10 in credits per month, not a fixed request count. At the Lite rate of $4 per 1k searches, that is about 2,500 searches, but Auto and Fast are $7 per 1k (about 1,428 searches) and Deep Search is $12–15 per 1k (about 666–833 searches). Credits reset on the 1st of each month and do not accumulate—unused credits never carry over. A one-time $10 onboarding bonus is available for the first team. No credit card is required, and every endpoint is accessible on the free tier.

What is Exa's rate limit, and can I raise it?

Search and Answer are capped at 10 QPS per team, Deep Search at 5 QPS, Contents at 100 QPS, and Agent at 5 QPS with 50 concurrent runs. The limit applies to the team as a whole across all API keys, so adding keys does not raise it. The limit rises to 25 QPS automatically for 90 days after purchasing $1,000 in credits within a 30-day window—spending $1,000 does not qualify, only buying it does. Beyond 25 QPS requires an Enterprise arrangement. For agent fleets or batch jobs, 10 QPS is a real bottleneck: a published GAIA validation run recorded 1,341 HTTP 429 errors from Exa, 44% of all tool failures in that run.

Does Exa search the live web in real time?

No. Exa searches its own index, built from a crawl of more than 500 billion pages. Recency is bounded by crawl cadence, not by live retrieval—a page published minutes ago may not be indexed yet. The Contents endpoint returns what the crawler last captured for a known URL, not a fresh fetch. For workflows that require the live version of a page, Exa is often paired with Firecrawl, which renders JavaScript on a live fetch. The architectural trade-off is accuracy on semantic and entity queries versus freshness on newly published content.

Does Exa search support pagination?

No. numResults accepts 1 to 100 with a default of 10, and the API returns that many results and stops. There is no cursor or offset for retrieving the next page. To exhaustively enumerate results—for competitive research, list-building, or due diligence—the caller must issue multiple queries with different phrasings and deduplicate client-side. Separately, the company and people categories do not support startPublishedDate, endPublishedDate, or excludeDomains; using them returns HTTP 400. These are documented spec constraints, not bugs.

Is Exa better than Tavily or Brave for agent search?

It depends on the query type and the benchmark. On Exa-run entity-lookup benchmarks, Exa's top-result precision is substantially higher than Tavily's (75.5% vs. 40.5% on people profiles, 81.5% vs. 61.3% on company lookups). But on the independent AIMultiple agentic search benchmark of 100 AI/LLM queries, Exa (14.39), Brave (14.89), Firecrawl (14.58), and Parallel Search Pro (14.21) are statistically indistinguishable because their confidence intervals overlap. In the Artificial Analysis Search Index for October 2026, Exa auto scored 74, behind Parallel Search advanced (75) and Perplexity Search (80). Exa is a strong default for semantic and entity search; it is not a universal leader across every workload.

Alternative Tools

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