People Data Labs vs Seamless.AI (2026): Data, Pricing and API Compared

People Data Labs (PDL) is a data API priced per match, with a public entry price. Seamless.AI is a sales platform with an API attached, priced in credits with no public dollar figure.

Verdict

• Pick People Data Labs if you are a developer who wants raw profiles, a price you can read and a miss that costs nothing. Its entry plan is $98 a month, and there are no seats.
• Pick Seamless.AI if reps need a Chrome extension and a dialer, or if you want an official MCP server with 57 tools. One credit covers a contact's email and phone together.
• Pick neither if you need volume through an API at a price you can read. Neither publishes a price at 1M records. LeadOcean is one option: Pro is $499 a month, flat.

Side by side

Data and coverage

PDL lists 2.47B person profiles and 76.6M companies. Seamless.AI claims 2.2B+ verified contacts and 121M+ companies. The two counts are not like for like.

PDL's 2.47B is its full person dataset, and only part of it carries contact data. Its email dataset is 592M profiles and its mobile dataset is 470M. Seamless.AI counts "verified" contacts, and it does not say how it verifies them.

Seamless.AI claims 1.6B+ verified business emails, nearly three times PDL's email count. On mobile numbers the two are close: 448M+ claimed against 470M. PDL also reports 764M profiles with any phone number.

All of these are vendor claims, not audited counts. The claims have also moved. Seamless.AI's older pages cited 1.3B contacts and 414M mobiles, and the current pages say 2.2B and 448M.

Company data is a separate question. PDL's company plan starts at $100 a month for 1,000 records (PDL pricing, September 2026). Seamless.AI charges 1 credit per company researched, at a dollar price it does not publish.

Match rate also depends on what you feed in. PDL takes a profile URL, an email, a phone or a PDL ID, and says more inputs raise the chance of a match (PDL docs, September 2026). Seamless.AI's direct research path takes a name and a company, which is a looser key than a profile URL.

Test on your own list before you buy. Send the same 500 people through each free plan and compare match rates. PDL's Free plan obscures contact data, so you pay to see its emails and phones. Seamless.AI's Free license has 50 credits, which is enough for 50 people.

API and developer experience

Both are REST APIs. PDL answers in one synchronous call. Seamless.AI research is asynchronous: you submit, then poll or wait for a webhook.

PDL sends a key in the X-Api-Key header to GET /v5/person/enrich. A match returns 200 and is billed. A miss returns 404 and is not (PDL docs, September 2026).

curl -G "https://api.peopledatalabs.com/v5/person/enrich" \
  -H "X-Api-Key: $PDL_API_KEY" \
  --data-urlencode "profile=https://linkedin.com/in/seanthorne"

Seamless.AI sends a key in a Token header. You submit POST /contacts/research with a name and company, and get back HTTP 202 and requestIds (Seamless.AI docs, September 2026).

curl -X POST https://api.seamless.ai/api/client/v1/contacts/research \
  -H "Content-Type: application/json" \
  -H "Token: $SEAMLESS_API_KEY" \
  -d '{"contacts":[{"contactName":"Jane Doe","companyName":"Acme Corp","title":"CTO"}]}'

You then call GET /contacts/research/poll with the request IDs until the status is done, error, missing or duplicate. Seamless.AI advises a 2 to 5 second poll interval.

Rate limits shape how each one scales. PDL limits are per key, in a fixed one-minute window. Enrichment allows 1,000 a minute on paid plans, but Person Search allows only 10 a minute by default (PDL usage limits, September 2026).

Seamless.AI's default is 60 requests a minute per endpoint, shared by every key and user in the organization. A search page returns up to 500 contacts, and one research request takes up to 500 records (Seamless.AI docs, September 2026). At that size, 1,000,000 records is 2,000 research calls, about 34 minutes of request windows, plus polling.

On MCP, only Seamless.AI has an official server. It lives at https://mcp.seamless.ai/mcp, takes OAuth 2.1 or an API key, and exposes 57 tools. Search tools use no credits and research tools do (Seamless.AI MCP docs, September 2026). PDL lists no MCP server, and only community servers exist (PDL llms.txt, September 2026).

Pricing

PDL charges per credit, and one credit is one matched profile. Seamless.AI charges one credit per record researched, and the dollar price of a credit is not published. To compare them, count credits first.

At 10,000 records a month

For PDL, 10,000 profiles is 10,000 credits. PDL says Pro profiles cost about $0.20 to $0.28 each, depending on volume and plan. So 10,000 x $0.20 = $2,000 and 10,000 x $0.28 = $2,800 (PDL blog, February 2026). PDL does not publish the exact price per credit at 10,000 credits a month. Treat this as a range. The credit selector in your PDL dashboard shows the price for your volume.

For Seamless.AI, 10,000 contact researches is 10,000 credits, and one credit covers the email and phone together. A Pro license carries 10,000 credits a month (Seamless.AI credit docs, September 2026). If you search first, add 10,000 / 10 = 1,000 credits, so you need 11,000 and a second license or a bulk pool.

Seamless.AI publishes no dollar price for a license, so no cost can be worked out (Seamless.AI pricing, September 2026). Credits refresh on the contract date, and the docs state no rollover. The docs do not say whether a research request that finds nothing is charged.

At 1M records a month

For PDL: no public 1M price. Self-serve Pro stops near 100,000 person profiles, and above that PDL quotes Enterprise only (PDL blog, September 2026). Do not multiply the Pro rate out to 1M and call it a quote.

For Seamless.AI: no public 1M price. The volume is 1,000,000 credits, or 1,100,000 if every record comes from a search first. At 10,000 credits per Pro license, that is 100 licenses or a bulk pool, both quote only (Seamless.AI bulk credits, September 2026).

Contract terms matter at that size. Subscriptions are annual. Cancelling needs 60 days' notice before renewal, or it renews for 12 months (Seamless.AI terms, September 2026).

Where People Data Labs wins

• A price you can read. Pro starts at $98 a month, and the per-profile range is published. Seamless.AI sends you to a form.
• A miss is free. A 404 is not billed. Seamless.AI's docs are silent on missing results.
• Bulk files. An annual Data License delivers person data to S3, GCP or Azure (PDL docs, September 2026).
• Faster enrichment. 1,000 requests a minute on paid plans, against 60 for Seamless.AI.

Where Seamless.AI wins

• A sales workspace. Reps get the platform, and the API is one product among several. PDL is an API only.
• Official MCP. 57 tools, against none from PDL.
• Email and phone in one credit. A single credit covers both, and search costs 1 credit per 10 results.
• Bigger email and company claims. 1.6B+ business emails and 121M+ companies, against PDL's 592M and 76.6M.

If you need volume through an API

We build LeadOcean, so weigh this section accordingly. LeadOcean holds 693M people and 63M companies, and you reach them over REST and MCP. Free is 1,000 records, one-off, with no card. Pro is $499 a month, flat, with unlimited searches and lookups and a limit of 100 requests per second per key (LeadOcean pricing, September 2026).

For bulk work, POST /v1/exports returns up to 50,000 rows per request. The app also has an Exports page with a filter builder and CSV download (LeadOcean exports docs, September 2026). There is no sequencer or dialer. See the PDL alternatives roundup or the PDL alternative page for a line-by-line version.

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