80
Stack Score
Editorial pick✓ Verified working
Exa (formerly Metaphor)
Search engine for AI — semantic and link-prediction based.
Try Exa (formerly Metaphor)✓ Free trial available
Best for
Researchers and builders who need link-prediction style semantic search beyond keyword matching.
At a glance
- Pricing
- freemium
- Setup time
- 5 minutes
- Learning curve
- easy
- Last verified
- 5/22/2026
What we love
- ✓Genuinely new search modality
- ✓Cleanest "find similar" API
- ✓Strong for non-keyword queries
Where it falls short
- −Pricier than Tavily
- −Smaller index than Google
- −Less effective on common queries
Pricing
✓ Pricing verified Jun 21, 20263 tiers
Free
$0
1000 calls/mo
- ✓All endpoints
Starter
From $0.005
per request
- ✓Production scale
Pro
Custom
quote
- ✓Higher limits
- ✓SLA
Why we picked it
Exa is the search API for queries Google can't even handle — "essays similar to this one", "startups doing X in Europe". Genuinely novel.
Overview
Search engine for AI — semantic and link-prediction based. Researchers and builders who need link-prediction style semantic search beyond keyword matching.
Key features
- ●Neural link-prediction search
- ●Find similar URLs to a seed
- ●Find people / companies / papers
- ●Content retrieval + summarization
- ●Filters by date, domain, type
- ●Webhook + LangChain
- ●Research API
Best use cases
Find prospects similar to current customer
Seed URL → 20 similar companies.
Discover hidden research
Find papers/essays on a niche topic.
Integrations
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