6 Best Lookalike Company Search Tools in 2026 (Compared)

A lookalike company search tool takes one or more seed companies and returns other companies that resemble them. Marketers use it to build account lists from their best customers. Engineers and agent builders use it as an API call: seed in, ranked domains out.

This list is for the second group. We read each tool's public docs and pricing pages in September 2026 and asked the same questions of all six. Can I send a seed domain by API? Can an agent call it? What does a million results cost? We did not run paid searches, so there is no benchmark of match quality here. Test your own seeds before you buy.

If you already use one of these, we have pages on the Ocean.io alternative, the AI-Ark alternative, the Lusha API alternative and the ZoomInfo alternative.

TL;DR

Prices are monthly list price first, billed-yearly figure after it. Sources are in each section. "Records" means company results returned.

What we evaluated

• Seed input. How many seed companies you can send, and whether matching is a similarity model or a set of filters.
• API and MCP. A documented lookalike endpoint, and an MCP server an agent can call without custom glue.
• Rate limit. Requests allowed per second or minute on the plan you would actually buy.
• Price per result. What one returned company costs, and whether sizing a list first is free.
• Cost at 1M records a month. The published price for a million results. If there is no public price, we say so and do not multiply a rate out.

1. Ocean.io: best for similarity matching from seed domains

Ocean.io built its product around lookalike search. You pass seed domains in lookalikeDomains on POST /v3/search/companies, and it returns similar companies. A companyMatchingMode setting picks "precise", which matches on similar products and services using semantic similarity, or "broad", which matches companies in the same industries (Ocean.io docs, September 2026).

Results cost 0.2 credits each, and one request returns up to 10,000 results (Ocean.io docs, September 2026). Domains that Ocean.io cannot find come back in missingDomains, so you know which seeds were ignored. There is a separate preview endpoint and a people lookalike search that takes LinkedIn handles.

The catch is access. Self-serve API keys get 60 requests a minute and 1,000 a day (Ocean.io rate limits, September 2026). The pricing page is behind a bot check, so we could not read a plan price or a price per credit.

Pros

• A real similarity model, with a precise mode and a broad mode.
• Up to 10,000 results from one request.
• Lookalike search for people as well as companies.
• MCP server with 8 tools, billed at the REST credit rate (Ocean.io docs, September 2026).

Cons

• No public plan price or price per credit.
• Self-serve limit of 1,000 requests a day.
• Credit-based, so cost depends on a plan you cannot see.

Best for: teams that start from their best customers and want the closest matches.

Pricing: credit-based plans with no public price we could read. Search is 0.2 credits a result (Ocean.io credits docs, September 2026; Ocean.io pricing, September 2026).

2. CompanyEnrich: best for a priced lookalike endpoint

CompanyEnrich is an API-first company data service, and lookalike discovery is one of its headline features. POST /companies/similar takes a company by ID or domain and returns up to 100 similar companies per request. The POST route accepts extra filtering parameters, so you can narrow the matches (CompanyEnrich docs, September 2026).

It is also the only tool here that prices the endpoint in the open. Find similar costs 5 credits per company returned, and 5 credits if nothing matches. A free count endpoint sizes the result first, and a Scale-plan preview returns the top 25 for free (CompanyEnrich docs, September 2026).

The MCP server at mcp.companyenrich.com/mcp covers enrichment, search and find similar. Authentication is an API key as a bearer token (CompanyEnrich MCP docs, September 2026). The dataset is 33M+ companies, about half of LeadOcean's 67M.

Pros

• Public price: 5 credits per similar company.
• Free count of similar companies before you spend.
• MCP server with a find-similar tool.
• Extra filters on the similar endpoint.

Cons

• Lookalikes cost five times a normal search result.
• Rate limit is 60 requests a minute on Starter, 120 on Pro and 600 on Scale.
• Smaller company database.
• Extra credits beyond a plan are not priced publicly.

Best for: developers who want a documented lookalike endpoint with a price they can budget.

Pricing: Starter $49 a month for 5,000 credits, Pro $149 for 50,000, Scale $549 for 500,000. Annual plans exist but no annual figure is published. Scale buys 100,000 similar companies a month, and there is no public price at 1M (CompanyEnrich pricing, September 2026).

3. ZoomInfo (GTM AI): best for free lookalike search

ZoomInfo's developer platform, GTM AI, makes lookalike search a free operation. Find Similar Companies returns a ranked list of companies similar to a reference company, produced by a machine learning model. Search is free too. You pay one data credit when you enrich a record (ZoomInfo docs, September 2026).

That changes the economics. You can run many lookalike searches, look at the results, and spend credits only on the companies you keep. Each record is charged once per 12 months, so re-enriching it inside that window costs nothing extra.

ZoomInfo has an official MCP server that works with Claude, ChatGPT and Cursor. A free GTM AI account includes MCP and API access, 5 requests a second, and 1,000 data credits (ZoomInfo MCP docs, September 2026; GTM AI pricing, September 2026). We could not read ZoomInfo's platform plan prices, which sit behind a human check.

Pros

• Lookalike and plain search are free. You pay only to enrich.
• Official MCP server and API on the free tier.
• Ranked results from a trained model.
• Records are charged once per 12 months.

Cons

• Free tier is 5 requests a second and a 1,000-credit allowance.
• Credit price falls with spend: $0.45 for 100 credits, $0.25 at 100,000 (GTM AI pricing, September 2026).
• 25 records per enrichment call.
• No public price at 1M.

Best for: teams that want to explore lookalikes freely and pay only for the accounts they enrich.

Pricing: data credits pay as you go from $20, with no contract. List price per credit runs from $0.45 at 100 credits down to $0.25 at 100,000. A 70% first-purchase discount is a promotion, not list price (GTM AI pricing, September 2026).

4. LeadOcean: best for filter-based lookalikes plus people at flat volume

LeadOcean has no similarity model, and we want to be plain about that. Our lookalike method is firmographic: read the seed's industry, headcount range, country and funding, then search the company database on the same values. Every row is there for a reason you can read.

The free Lookalike Companies Claude skill runs this over the hosted MCP server. It reads the seed with get_company (1 record), then calls search_companies for up to 25 matches at 1 record each. If fewer than 10 come back, it drops one filter and tries again, and tells you which one.

Where LeadOcean fits is the step after the list. The company count GET /v1/companies/count is free and returns an exact total with breakdowns by industry, headcount band, HQ country, HQ state and NAICS. Then GET /v1/companies/{domain}/people pulls the people at each match. The database holds 67M companies and 693M people, with 34 company filters.

The MCP server has 13 tools and signs in with OAuth 2.1, with no key pasted into a chat (LeadOcean MCP docs, October 2026).

Pros

• Flat monthly price, no credits, no per-record price.
• Free exact company counts before you pull a row.
• Companies and the people behind them in one API and one MCP server.
• Rate limit of 5 requests a second on Free, 50 on Solo, 200 on Agency.

Cons

• No similarity score and no seed-based model. You need to know which filters matter.
• No preview of lookalike quality beyond reading the filters.
• Bulk CSV export is not on Free.

Best for: engineers and agents that build a company list by filters, then pull people at volume for one fixed bill.

Pricing: Free $0 for 1,000 records (one-off, no card), Solo $97 a month, Agency $497 a month, Platform $1,997 a month. Paid plans have a fair-use pace, not credits (LeadOcean pricing, October 2026). 1M company records fit inside Agency's 25M search records a month.

5. AI-Ark: best for the cheapest lookalike results

AI-Ark takes up to 5 seed companies in its company search. The same search costs 0.1 credits per result (AI-Ark docs, September 2026). That is the lowest per-record price in this list. AI-Ark also offers a "Job Role" filter, which finds companies by the people they employ, and a keyword mode that takes up to 5 sources.

The API is REST with an X-TOKEN header, and there is a hosted MCP server. The default rate limit is 5 requests per second per key. Custom limits start at 450,000 credits a month (AI-Ark docs, September 2026). One search retrieves up to 10,000 records.

The pricing page lists the lookalike finders in a plan comparison table, so check which plan includes them. AI-Ark is strongest as an account-finding step. Many teams export lookalike domains from AI-Ark and pull people elsewhere. Our AI-Ark alternative page walks through that split.

Pros

• 0.1 credits per company result, the cheapest here.
• Up to 5 seed companies per lookalike search.
• Lookalike finder for people as well as companies.
• Hosted MCP server.

Cons

• 5 requests per second by default.
• 10,000 records per search.
• The MCP server takes the API key in the URL query string (AI-Ark MCP docs, September 2026).
• Which plan includes the lookalike finder is not clear from the pricing page.

Best for: agencies and teams that run large account lists and want the lowest cost per lookalike company.

Pricing: Free with 100 credits a month. Usage-based $49 a month for 5,000 credits, with 20% off when paid annually. Plans above 30,000 credits list $2 to $4 per 1,000 credits (AI-Ark pricing, September 2026). There is no public price at 1M.

6. Lusha: best for reps who want lookalikes next to contacts

Lusha added lookalikes for both contacts and companies. The Lookalike API has two endpoints, POST /v3/contacts/lookalike and POST /v3/companies/lookalike. You send seed accounts, and it returns recommended matches by firmographics and characteristics. Both accept an exclude table, so you can drop customers you already have (Lusha docs, September 2026).

Credits are charged per successful result, but Lusha does not state the number in the pages we read. Lusha also says API lookalike availability depends on your plan and package.

The MCP server has two lookalike tools, lookalike_contacts and lookalike_companies (Lusha MCP tools, September 2026). Rate limits by plan are 40 requests a minute on Free and Starter, 50 on Pro and 300 on Premium and Scale (Lusha API guide, September 2026).

Pros

• Company and contact lookalikes in the same API and MCP server.
• Exclude table to avoid known customers.
• Pagination with a session ID kept for 30 days.
• Chrome extension and CRM apps for reps.

Cons

• Credits per lookalike result are not published.
• Lookalike API availability varies by plan and package.
• Low rate limits at the lower tiers.
• No public price at 1M.

Best for: sales teams that already work in Lusha and want lookalike accounts without a second vendor.

Pricing: Free with 40 credits a month. Starter is $49.90 a month, or $37.45 a month billed yearly for 4,800 credits a year. Scale is custom (Lusha pricing, September 2026).

Comparison table

How to choose

• You want the closest matches from a few seed customers. Start with Ocean.io, and test its precise mode against your own seeds.
• You want a price you can budget in code. CompanyEnrich: 5 credits per similar company, with a free count first.
• You want to explore a lot and pay only for what you keep. ZoomInfo's GTM AI, where search and find similar are free.
• You want the lowest cost per company. AI-Ark at 0.1 credits a result.
• You build lists from filters and then need people at volume. LeadOcean, with a flat bill and free counts.
• Your reps live in Lusha already. Use its lookalikes and skip a new vendor.
• You need both similarity and volume people data. Find accounts in Ocean.io or AI-Ark, then pull people from LeadOcean by domain.

Verdict

For similarity quality from seed domains, Ocean.io is the specialist, and ZoomInfo is the better pick if you want to search freely and pay only on enrichment. For a budget you can write down, CompanyEnrich publishes the price of a lookalike result and AI-Ark has the lowest. For an agent that builds a company list by filters and then needs the people there, LeadOcean gives a flat price and free counts. It will not rank by similarity. Lusha fits teams already inside Lusha.

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