Seamless.AI vs Hunter.io (2026): Data, Pricing and API Compared

Seamless.AI is the bigger database and a full prospecting workspace, so it fits reps who also want phones. Hunter is the cheaper, simpler way to find work emails by API, so it fits developers and small teams. At 1M records Hunter publishes a price ($6,900 once) and Seamless.AI does not.

Verdict

• Pick Seamless.AI if reps will prospect inside one tool and you want email and phone from a single credit, on a contract you negotiate with sales (Seamless.AI API page, September 2026).
• Pick Hunter if you mainly need work emails by domain or by name, through an API or in bulk, and you want a public price list (Hunter pricing, September 2026).
• Pick neither if you pull people and company data by API at volume and want one flat price. A credit meter and a quote form both get awkward there. LeadOcean is one option, covered below.

Side by side

Data and coverage

Seamless.AI claims far more people and more fields. It lists 2.2B+ verified contacts, 1.6B+ business emails, 448M+ mobile numbers and 121M+ companies, with 100+ data points on a profile (Seamless.AI API page, September 2026). These are vendor claims. No page we read says how they are counted, so test a sample before you trust them.

Hunter publishes no database size on its homepage (Hunter, October 2026). The data is addresses tied to domains and names, so it is narrower by design.

The two start in different places. Hunter starts from a domain you already know: Domain Search lists the addresses it found there, and Email Finder returns the likeliest address for a name. Seamless.AI starts from an audience. You search by title, seniority and company filters first, then research the records you want.

Phones are the clearest split. Seamless.AI sells email and phone in one credit and claims a large mobile base. Hunter's responses carry an optional phone_number field, but its docs list no phone endpoint and no phone count (Hunter API docs, September 2026).

API and developer experience

Both have a REST API and both send a key in a header. Seamless.AI researches in two steps: you submit records, then poll for the result or receive it by webhook. Hunter answers in one call. The examples use placeholders (Acme, Jane Doe).

Seamless.AI, research one contact by name and company.

curl --request POST \
  --url "https://api.seamless.ai/api/client/v2/contacts/research" \
  --header "Token: $SEAMLESS_API_KEY" \
  --header "Content-Type: application/json" \
  --data '{"contacts":[{"contactName":"Jane Doe","companyName":"Acme"}]}'

The body takes up to 500 contacts, and the call returns a request id to poll. The OpenAPI reference lists the base as /api/client/v2, while the rate-limit page examples still show /v1 (Seamless.AI docs, September 2026). Polling and reading org records cost no credits. A search costs 1 credit per 10 results returned.

Hunter, find an email by name and domain.

curl --request GET \
  --url "https://api.hunter.io/v2/email-finder?domain=acme.com&first_name=Jane&last_name=Doe" \
  --header "X-API-KEY: $HUNTER_API_KEY"

The response has the address and a confidence score (Hunter API docs, September 2026). A rate-limited call gets a 403, while a 429 means you used up your credits. That is the reverse of what most clients expect.

Both have a hosted MCP server. Seamless.AI's has 57 tools across 13 domains, and search tools use no credits while research tools do (Seamless.AI MCP docs, September 2026). Hunter's is included on every plan and spends your plan credits (Hunter MCP, September 2026).

Throughput matters at volume. At 500 records a call and 60 requests a minute, 1,000,000 records is 2,000 search calls and 2,000 research calls, about 34 minutes each, in separate windows, plus polling. Hunter's Email Finder takes one lookup per call: 1,000,000 / 500 a minute = 2,000 minutes, about 33 hours. Bulk Email Finder files avoid that.

Pricing

Hunter prints every price. Seamless.AI prints none. Its pricing page is a quote form. Standalone API pricing is not published, because keys come bundled with plan tiers or as an add-on (Seamless.AI pricing, September 2026).

What Seamless.AI does publish is credits. Free is 50 credits with no refill. Basic is 250 credits a month. Pro is 10,000 credits a month per license, refreshed on the contract date (Seamless.AI credit docs, September 2026). Subscriptions are annual, and cancelling needs 60 days' notice before renewal or it renews for 12 months (Seamless.AI terms, September 2026).

At 10,000 records a month

• Seamless.AI: 10,000 research credits is one Pro license's monthly allowance. If each record first comes from a search, add 10,000 / 10 = 1,000 credits, so 11,000. Dollar price: not published.
• Hunter: Growth includes 10,000 credits for $149 a month, or $104 a month billed yearly (Hunter pricing, September 2026). Only emails found use a credit.

At this size Hunter is the only one you can price from a web page. Seamless.AI may cost less or more. Ask for a quote and compare it with $149.

At 1M records

• Seamless.AI: no public 1M price. 1,000,000 contact researches is 1,000,000 credits, or 1,100,000 with search first. At 10,000 credits per Pro license that is 100 licenses, or a bulk credit pool. Both are quote only (Seamless.AI docs, September 2026).
• Hunter: 1,000,000 Search credits on the Data Platform cost $6,900, paid once and valid 12 months, which is $0.0069 a credit (Hunter Data Platform, September 2026). Above 1M is custom.

The all-in-one route costs more on Hunter. Scale is $299 a month for 25,000 credits, plus 975,000 pack credits at up to $0.02 each is $19,500, about $19,799 in all. Packs cap at 180,000 per purchase (Hunter help, September 2026). At 1M, use the Data Platform.

Note what one credit buys. Hunter's $6,900 buys 1M emails. Seamless.AI's credit buys the email and the phone together, so the two are not the same unit.

Where Seamless.AI wins

• A much larger claimed database, with phones, firmographics and 100+ data points a profile.
• Email and phone from one credit, where Hunter has no phone endpoint.
• A prospecting workspace: its homepage lists calling, emailing and a Chrome extension (Seamless.AI, October 2026).
• Search by audience: title, seniority and company filters before you spend credits.
• Negotiated bulk credit pools for very large pulls.

Where Hunter wins

• A public price at every size, and $6,900 for 1M credits against a quote.
• Cheaper to start: Starter at $34 a month billed yearly, plus a Free plan that renews 50 credits each month.
• A simpler API: one GET, a synchronous answer, no polling.
• No charge when nothing is found, and repeat lookups in a billing period are not charged again.
• A higher rate limit, 500 a minute on Email Finder against 60 a minute per endpoint.
• Bulk Email Finder takes 50,000 rows per file, and the MCP server is on every plan.

If you need volume through an API

LeadOcean is a data API and MCP server with no seats and no credits. It is not a sales workspace, so reps would still need a sending tool. Pro costs $499 a month flat, with unlimited searches, enrichments and lookups, and the Free plan gives 1,000 records one-off with no card. Both plans get the same REST API, a 12-tool MCP server and 100 requests per second per key. POST /v1/exports returns up to 50,000 rows per request (LeadOcean exports docs, September 2026). A very large month can be paced down past the fair-usage line, so ask support about headroom. Compare it on a list you already know, then read Seamless.AI alternatives and pricing.

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