v1
latestOpenAPI 3.1.02026-07-22103475.9 KBSearch Lookalikes
Find lookalike companies from either a natural-language description or a set of seed company websites, with optional firmographic filters.
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Use it for queries such as:
- Healthcare companies building with voice AI
- Companies that provide customer support software for B2C
- Companies that build workflow automation for non technical industries
Or supply 1-10 seed company websites and let OpenFunnel synthesize the query for you:
- seed_domains=datadog.com&seed_domains=grafana.com&seed_domains=dynatrace.com
You can also restrict results to your ICP by applying filters for company size, funding stage, and headquarters country.
Two input modes
At least one of query or seed_domains is required. Both can be combined for a hybrid trait.
- Natural language (query): describe the kind of company you want. Best when you can articulate the trait in 1-2 sentences.
- Seed-based discovery (seed_domains): pass up to 10 company websites and OpenFunnel uses them to synthesize the lookalike query for you. Best when you can name a few example customers but struggle to phrase what they have in common.
- Both together: pass seed_domains AND query - the query becomes a must-have angle layered on top of the seeds (e.g. seeds=[datadog.com, grafana.com] + query="cloud monitoring and observability tools" → synthesized trait targets cloud monitoring tools).
With seed_domains, the response echoes back the LLM-synthesized derived_query, plus resolved_seed_domains (seeds that landed in our index) and unresolved_seed_domains (seeds we couldn't find - skipped silently as long as at least one resolved).
Omitting filters
If you omit filters, search runs across all company sizes, funding stages, and supported locations. Use the optional firmographic filters below to restrict results to your ICP.
Discovering available firmographics
The funding_stages, locations, min_employees, and max_employees filters accept a fixed set of values. Fetch the current set via GET /api/v1/account/firmographic-options it returns the accepted funding_stages labels, the supported HQ locations (code + name), and the min/max employee bounds.
Credits
1 credit per company returned. Empty result sets are free. The exact amount billed is echoed back in credits_consumed on the response. The LLM trait synthesis used by seed_domains is included - no extra charge.
The response includes a derived_query field with the LLM-synthesized trait so you can see exactly what was searched.
Query parameters
Describe the kinds of companies you want to find. Required unless seed_domains is provided. When both are supplied, the query is used as a must-have angle on top of the trait synthesized from the seeds.
Up to 10 seed company websites/domains (e.g. datadog.com, https://www.grafana.com). When provided, OpenFunnel uses them to synthesize the lookalike query for you. Protocol / www. prefixes are normalized automatically. Unresolved seeds are skipped silently as long as at least one resolves. Repeat the parameter to send multiple values.
Maximum number of companies to return. Default 10, max 100. For larger result sets (up to 10000), use the async bulk endpoint POST /api/v1/account/search-lookalikes-bulk.
Minimum employee count, inclusive.
Maximum employee count, inclusive.
Funding stages to include. Repeat the parameter to send multiple values.
Headquarters country filter using ISO 3166-1 alpha-3 codes (e.g. USA, GBR, IND, DEU). Top 30 by company volume: USA, GBR, CHN, FRA, IND, DEU, BRA, BEL, ESP, CAN, AUS, NLD, ITA, NOR, ZAF, MEX, TUR, CHE, ARE, POL, SWE, IDN, ARG, PAK, COL, PRT, JPN, CHL, NGA, AUT. Pass EU to expand to all 27 EU member states. Repeat the parameter to send multiple values. Full list of 250 codes via GET /api/v2/tech/country-options (under Agent Helpers).
Headers
Response
Successful Response