best-of · Evidence checked 2026-09-02
The best search API is the smallest layer you can verify
A practical, evidence-led decision guide. Product capabilities and limits are separated from anything that would require hands-on testing.
There is no universal best AI search API. There is a costly architectural mistake: buying an answer endpoint when the application only needs ranked URLs, or assembling five retrieval calls when a research endpoint already meets the quality target.
| API | Shortlist it for | Hard question |
|---|---|---|
| Tavily | agent-oriented search and extract workflows | What does one completed task consume? |
| Exa | semantic discovery and content retrieval | Does it recall the known niche corpus? |
| You.com | selectable Search, Contents, Answer and Research layers | Which layer avoids duplicated work? |
| Brave Search | independent-index retrieval and grounded answers | Does regional/long-tail coverage pass? |
| Kagi | premium search results and configurable ranking | Is $12/1,000-query retrieval justified? |
| Perplexity | answer/search APIs with visible sources | Are token and search charges modeled together? |
Benchmark 200 frozen queries with a known-relevant URL set, freshness timestamps and prohibited domains. Record recall@10, primary-source rate, latency p50/p95, empty results, duplicate domains, extracted bytes and total bill. For answer endpoints, add claim-support review; for raw search, add your own model cost.
Primary action: run the same versioned fixture against the smallest viable endpoint from each provider and buy on cost per accepted application answer—not price per call.