What Is a B2B Data API?

A B2B data API is a web service that returns records about businesses and the people who work at them, whenever your code asks. This page defines the term, walks through a request, and shows where LeadOcean fits.

Key takeaways

• A B2B data API returns people and company records as JSON over HTTP. You send a query and get rows back.
• It is a data source, not a sales tool. There is no inbox, dialer or sequencer inside it.
• Most calls fall into three jobs: search for records, enrich a record you already know, and export a large list.
• LeadOcean exposes all three on one API and one MCP server, with a free plan of 1,000 records.

What it is

A B2B data API is an interface that lets software request people and company records, such as name, job title, employer, email and phone, and receive them in a structured response.

The data behind it is a large database of professionals and companies, kept current by the provider. The API is the front door. You never see the database, only the answers to your queries.

"B2B" matters. The records describe working people and the businesses they work for, not consumers. Typical fields are job title, seniority, company domain, industry, headcount and a work email.

How it works

Every B2B data API follows the same loop. You authenticate, you ask, and you get records back.

1. Authenticate. You send an API key with each request. LeadOcean reads it from the x-api-key header.
2. Pick the call. Search finds records that match filters. Enrich fills in a record you partly know. Export pulls a big list in one job.
3. Send the query. You pass filters or an identifier, such as a LinkedIn URL or an email.
4. Read the response. The API returns JSON. Each person or company returned counts as one record against your plan.
5. Store or act on it. Your code writes the rows to a database, a spreadsheet or a CRM, or hands them to an agent.

A worked example

Say you run outbound for a fictional company, Acme, and you want to know who sits in the sales team at a target account, acme.com. You make one call.

curl "https://api.leadocean.io/v1/companies/acme.com/people" \
  -H "x-api-key: $LEADOCEAN_API_KEY"

The response is a page of thin records for people at that domain, each with a title and a level but no contact fields. Each person returned counts one record. You pick one person and enrich them by person_id to get the email and its status.

curl -X POST "https://api.leadocean.io/v1/people/enrich" \
  -H "x-api-key: $LEADOCEAN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"person_id": "PERSON_ID", "reveal_email": true}'

Two calls, no browser, no copy and paste. The same two calls work from a script, a cron job or an AI agent.

B2B data API vs sales platform

People mix the two up because many vendors sell both. They solve different problems.

A sales platform often sits on top of a data source. A data API is the layer underneath, sold on its own. If you already have a CRM and a sending tool, you probably need the data layer only.

When it matters

Enriching your CRM

A CRM full of half-filled records wastes rep time. A data API fills the gaps from an email or a LinkedIn URL, on a schedule, without a person doing it. You decide which fields to overwrite and which to keep.

Building lead lists in code

Search takes filters such as job title, country, industry and seniority. You can size a list before you pull it, and pull it again next month as people change jobs. Code makes the list repeatable.

Feeding AI agents

An agent needs live records, not a stale export. A data API with an MCP server lets Claude or another agent search and enrich directly, with no glue code. LeadOcean's server is at https://api.leadocean.io/mcp and signs in with OAuth, so no key is pasted.

Replacing a monthly list purchase

Buying a list once a quarter means paying for rows you never use. An API lets you pull only the segment you need, when you need it. You pay for what you return, or a flat fee, depending on the vendor.

How LeadOcean handles it

LeadOcean is a B2B data API with a hosted MCP server and an app for exports. The base URL is https://api.leadocean.io, and every call takes the x-api-key header.

The calls map to the three jobs from above:

• Search: /v1/people/search and /v1/companies/search, with a flat JSON body of filters. Results come back 1 to 100 at a time, with a cursor to page forward.
• Enrich: POST /v1/people/enrich takes exactly one of linkedin_url, email, phone or person_id. POST /v1/companies/enrich does the same for a company. A person we hold nothing for returns a 404 and costs nothing.
• Export: POST /v1/exports pulls up to 50,000 rows per request. The Exports page in the app at app.leadocean.io has a filter builder, a column picker, the record price before you start, and a CSV download.

The database holds 693M people, 366M with an email and 166M with a phone number, plus 63M companies (as of 2026-09-23). It is refreshed monthly, and each record carries its own fetched_at date. Filters number 50 for people and 34 for companies.

You can size any list for free before you spend a record. Send count=true as a query parameter with limit set to 1. meta.total is capped at 100,000.

curl -X POST "https://api.leadocean.io/v1/people/search?count=true" \
  -H "x-api-key: $LEADOCEAN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "jobLevel": ["VP"],
    "jobFunction": ["Sales & Business Development"],
    "country": ["CA"],
    "limit": 1
  }'

The response has an empty data array and meta.countOnly set to true. Drop count=true and raise limit to pull rows. Each person returned counts as one record.

The free plan gives 1,000 records, one-off, with no card. Pro is $499 a month, flat, with no per-record price and 100 requests per second per key. See pricing for the details. To compare providers, read the best B2B data APIs, the best B2B data providers with an API and the best company data APIs.

LeadOcean has no rep workspace, sequencer, dialer or CRM. It supplies the data. You bring the tools that use it.

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