# Seamless.AI, free license, POST /contacts/research: Reverse email lookup API

> Turn a work or personal email address into a full B2B profile: name, title, company, seniority, phones, LinkedIn, and job history.

Seamless.AI's reverse email lookup API on its Free License plan. It costs $0.00 per 1,000 people. It returns 3 of the 13 key fields we check: Experience, Location, Photo.
We haven't run Seamless.AI through [our reverse email lookup API benchmark](https://datacircle.dev/best-reverse-email-lookup-api.txt) yet.
This plan is free. We rank 396 plans for reverse email lookup APIs by price. Half the plans cost $24.875 per 1,000 people or less.
[Minerva's $400 monthly plan](https://datacircle.dev/reverse-email-lookup-apis/minerva/400-monthly/llms.txt) costs the least per 1,000 people. Minerva's reverse email lookup API costs nothing beyond the plan price.
[Village's $25 pack (Reverse Lookup by Email, cached only)](https://datacircle.dev/reverse-email-lookup-apis/village/25-pack-1000-credits-post-v2-people-enrich-by-email-reverse-lookup-by-email-cached-only/llms.txt) covers any number of people. Village's $25 pack costs less up front than Minerva's $400 monthly plan.
[GetProspect](https://datacircle.dev/reverse-email-lookup-apis/getprospect/399-monthly-growth-50k-post-v2-people-enrich/llms.txt), [Village](https://datacircle.dev/reverse-email-lookup-apis/village/1-monthly/llms.txt) and [treg](https://datacircle.dev/reverse-email-lookup-apis/treg/top-up-from-200/llms.txt) are the best reverse email lookup API providers in the Datacircle benchmark.

- This page: https://datacircle.dev/reverse-email-lookup-apis/seamless-ai/free-license-post-contacts-research
- [Reverse email lookup API: 30+ providers compared](https://datacircle.dev/best-reverse-email-lookup-api.txt)
- Get it: https://seamless.ai/pricing-inquiry?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- Request: `POST https://api.seamless.ai/api/client/v1/contacts/research`
- API key: with the plan, on https://seamless.ai/pricing-inquiry?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- Its API docs: https://docs.seamless.ai/api-catalog/email-to-profile?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing#reference
- Sold by: Seamless.AI (https://seamless.ai?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing)
- Checked: 2026-11-03

## In the answer

- Completeness: 23%
- Experience: ✓
- Location: ✓
- Photo: ✓

## Price

- $ per 1,000 people: $0.00
- Per: result
- Billing: free

## Aggregators

- Aggregators: none

## Charges

- Also pays for: Get Org Contacts: no credits, 60 requests per minute · Get Org Companies: no credits, 60 requests per minute · Look up location filter values: no credits, 60 requests per minute · from the same budget: Search contacts · Search companies · Research companies · Research a single contact

## Overage

- Units cap: hard

## Not found

- $ per 1,000: $0.00

## In their words

- Their pitch: Turn a work or personal email address into a full B2B profile: name, title, company, seniority, phones, LinkedIn, and job history.

## Data

- Freshness: live
- Keep data: You may not: [...] (iii) Use the API to harvest, aggregate, or cache data not expressly authorized by Seamless. [...] You may not: (i) Store Seamless data longer than necessary to fulfill a legitimate business purpose [...] Upon termination, you must (i) Cease all use of the API, (ii) Delete all Seamless data in your possession, and (iii) Certify such deletion upon request. [...] We may request that you delete the personal information of individuals who have requested that their personal information be deleted. Upon request from Seamless, you agree to take all reasonable and appropriate steps to promptly and securely delete the relevant Seamless Data in your possession, custody or control.
- Use data: Seamless grants you a non-exclusive, non-transferable, non-sublicensable, revocable-at-any-time license to access and use the API solely for the purpose of developing, testing, and operating applications (“Developer Applications”) that interact with Seamless’s platform. You may not: (i) Use the API in any manner beyond the scope of this Agreement, (ii) Create an API client that functions as a substitute for Seamless’s core platform or competes with our services [...] You shall not: [...] (v) Use the API to collect sensitive personal information (e.g., SSNs, payment data), (vi) Send spam or unsolicited communications using API-derived data, or (vii) Exceed daily rate limits or create bulk scraping tools. [...] You may not: [...] (ii) Share, sell, or resell any Seamless data to third parties, and/or (iii) Use API data for user profiling, segmentation, or advertising without applicable consent. [...] You agree to access, use, disclose, retain and otherwise process Seamless Data only for the purpose of supporting business-to-business (“B2B”) development opportunities, including for identifying and researching prospective or existing B2B sales, marketing or recruiting opportunities for your business (collectively, the “Permitted Purposes”) and only as otherwise permitted by these Terms. [...] You are strictly forbidden from accessing, using or otherwise processing Seamless Data: For your personal, family or household purposes, or in connection with any non-B2B customers or prospects, In any unlawful, biased, fraudulent or discriminatory manner or for purposes of tracking, profiling or surveilling individuals, To send fraudulent or unlawful communications to individuals or entities, or To sell, rent, license, release, disclose, distribute, disseminate, sublicense, transfer, or otherwise make available, in whole or in part, any Seamless Data to a third party for monetary or other valuable consideration, or otherwise incorporate any portion of Seamless Data into your own or others’ products or services. [...] you will not use any Seamless Data or the Services for any purpose regulated under the Fair Credit Reporting Act (“FCRA”), 15 U.S.C. § 1681b [...] You further agree that you will not: [...] Integrate Seamless Data into any customer relationship management, marketing automation, or sales enablement platform to allow unauthorized users to access or use Seamless Data [...] You may not sell or publicly display or distribute any Seamless Content or otherwise use the Seamless Content in a manner not expressly permitted in these Terms without Seamless’s prior written consent. [...] SEAMLESS'S COMPETITORS ARE PROHIBITED FROM ACCESSING OR USING THE SERVICES IN ANY WAY, EXCEPT WITH SEAMLESS'S PRIOR WRITTEN CONSENT.

## Plan

- Pay: $0
- You get: 50 credits
- Enough for: 50 results, once

## Rate limit

- Per second: 1
- Batch: 500

## Speed

- Answer: by polling or webhook

## The call

- You send: contacts[].email. Optional: listIds, skipDeduplicationCheck
- Method: POST
- Path: /contacts/research

## About the plan

- Plan: Free License
- Who can get it: anyone 18 or over, for B2B purposes, not a competitor of Seamless.AI

## The 167 fields the plan's answer can hold

success, request ID, search result ID, status, message, contact ID, username, created at, updated at, first name, middle name, last name, full name, original name, company name, original company, company description, company founded year, company industry, SIC code, NAICS code, company staff count, company size, company staff count range, company annual revenue, company domain, company revenue, company revenue range, company LinkedIn URL, company LinkedIn ID, job title, department, seniority, LinkedIn URL, LinkedIn Sales Navigator URL, LinkedIn Recruiter URL, location city, location state, location post code, location county, location country, location state code, location country code, location country alpha-2, location country alpha-3, location country numeric, location, location timezone, location timezone offset, location timezone abbreviation, company street, company street 2, company street 3, company location city, company location state, company post code, company county, company location country, company state code, company country code, company country alpha-2, company country alpha-3, company country numeric, company location, city, state, country, company city, company state, company country, timezone, timezone abbreviation, local time, website, email domain, image, advertising intelligence URL, Alexa score URL, company news URL, employee reviews URL, Google Finance URL, Google research URL, job postings URL, local sports teams URL, local weather URL, paid search intelligence URL, paid search keywords URL, search marketing intelligence URL, SEC filings URL, SEO research URL, similar websites URL, social media mentions URL, social media posts URL, social posts URL, website audit URL, website audit 2 URL, website grader URL, web technologies URL, WHOIS URL, Wikipedia URL, Yahoo Finance URL, former company, former title, former started at, former ended at, title started at, started at current company, time at role, time at company, job history company name, job history title, job history started at, job history ended at, job change alert, company type, stock ticker, API research ID, news title, news URL, news date, news type, company funding total, company latest funding date, company latest funding classifications, additional data, email, personal email, email 1, email 1 selected, email 1 total AI score, email 1 email AI status, email 2, email 2 total AI score, email 2 email AI status, email 3, email 3 total AI score, email 3 email AI status, contact phone 1, contact phone 1 total AI score, contact phone 1 type, contact phone 2, contact phone 2 type, company phone 1, company phone 1 total AI score, company phone 1 type, company phone 2, company phone 2 total AI score, company phone 2 type, company phone 3, company phone 3 total AI score, company phone 3 type, researched at, record type, tags, list added at, is DNC some, is DNC all, is DNE some, is DNE all, contact phone 1 is DNC, contact phone 2 is DNC, contact phone 3, contact phone 3 type, contact phone 3 is DNC, company phone 1 is DNC, company phone 2 is DNC, company phone 3 is DNC

## Seamless.AI's plans (4)

- [Seamless.AI, free license, POST /contacts/research](https://datacircle.dev/reverse-email-lookup-apis/seamless-ai/free-license-post-contacts-research/llms.txt): $0.00 per 1,000, 23% complete, live
- [Seamless.AI, contact us, Pricing inquiry, POST /contacts/research](https://datacircle.dev/reverse-email-lookup-apis/seamless-ai/contact-us-pricing-inquiry-post-contacts-research/llms.txt): 23% complete, live
- [Seamless.AI, contact us, Basic License, POST /contacts/research](https://datacircle.dev/reverse-email-lookup-apis/seamless-ai/contact-us-basic-license-post-contacts-research/llms.txt): 23% complete, live
- [Seamless.AI, contact us, Pro License, POST /contacts/research](https://datacircle.dev/reverse-email-lookup-apis/seamless-ai/contact-us-pro-license-post-contacts-research/llms.txt): 23% complete, live

## Seamless.AI's calls for this API (2)

- `POST /contacts/research`: [Seamless.AI, free license, POST /contacts/research](https://datacircle.dev/reverse-email-lookup-apis/seamless-ai/free-license-post-contacts-research/llms.txt)
- `POST /search/contacts`: [Seamless.AI, free license, POST /search/contacts](https://datacircle.dev/reverse-email-lookup-apis/seamless-ai/free-license-post-search-contacts/llms.txt)

## Seamless.AI's APIs (7)

- [Seamless.AI: LinkedIn profile API pricing, 4 plans](https://datacircle.dev/linkedin-profile-apis/seamless-ai/free/llms.txt)
- [Seamless.AI: company discovery API pricing, 4 plans](https://datacircle.dev/company-discovery-apis/seamless-ai/free/llms.txt)
- [Seamless.AI: company enrichment API pricing, 4 plans](https://datacircle.dev/company-enrichment-apis/seamless-ai/free/llms.txt)
- [Seamless.AI: email finder API pricing, 4 plans](https://datacircle.dev/find-email-apis/seamless-ai/free/llms.txt)
- [Seamless.AI: phone finder API pricing, 4 plans](https://datacircle.dev/find-phone-apis/seamless-ai/free/llms.txt)
- [Seamless.AI: people search API pricing, 4 plans](https://datacircle.dev/people-search-apis/seamless-ai/free/llms.txt)
- [Seamless.AI: reverse email lookup API pricing, 4 plans, POST /contacts/research](https://datacircle.dev/reverse-email-lookup-apis/seamless-ai/free-license-post-contacts-research/llms.txt)

## Seamless.AI: reverse email lookup API alternatives

- [Village, free, POST /v2/people/enrich/by-email, Reverse Lookup by Email, realtime only](https://datacircle.dev/reverse-email-lookup-apis/village/free/llms.txt): $0.00 per 1,000, 31% complete, live
- [DeBounce, free](https://datacircle.dev/reverse-email-lookup-apis/debounce/free/llms.txt): $0.00 per 1,000, 8% complete, live
- [BetterEnrich, free](https://datacircle.dev/reverse-email-lookup-apis/betterenrich/free/llms.txt): $0.00 per 1,000, 15% complete, live
- [FullEnrich, free](https://datacircle.dev/reverse-email-lookup-apis/fullenrich/free/llms.txt): $0.00 per 1,000, 62% complete, live

## Sources

From each provider's own pricing page and docs, and from what providers tell us. We read this row from these pages on 2026-11-03.

- https://docs.seamless.ai/api-catalog/contact-enrichment?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://docs.seamless.ai/api-catalog/data-dictionary?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://docs.seamless.ai/api-catalog/email-to-profile?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://docs.seamless.ai/api-reference/v1/contact-research/poll-contact-research?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://docs.seamless.ai/api-reference/v1/contact-research/research-contacts?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://docs.seamless.ai/core-concepts/rate-limits-and-credits?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://gist.githubusercontent.com/JustinAlia/6ff38a671f5f79895444b77c57f3afff/raw/openapi.json?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://seamless.ai/customers/education/articles/seamless-ai-api-overview?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://seamless.ai/customers/education/articles/seamless-ai-credit-and-license-types?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://seamless.ai/policies/public-api-terms-of-use?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://seamless.ai/policies/terms-of-use?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://seamless.ai/pricing-inquiry?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing
- https://seamless.ai/products/api?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=reverse-email-lookup-api-pricing