# Leadbase, free: Email finder API

> Find work email addresses and direct phone numbers using an identifiable professional profile.

Leadbase's Free plan for the email finder API costs $0.00 per 1,000 emails. We check each provider's docs for 10 fields: Verification, Confidence, Catch-all domain, Where found and 6 more. Leadbase's docs list none of the 10.
We haven't run Leadbase through [our email finder API benchmark](https://datacircle.dev/best-email-finder-api.txt) yet.
This plan is free. We rank 1,846 plans for email finder APIs by price. Half the plans cost $20.00 or less per 1,000 emails. [See the best free email finder API plan.](https://datacircle.dev/best-email-finder-api.txt)
[Lakewave's $19 monthly plan](https://datacircle.dev/find-email-apis/lakewave/19-monthly/llms.txt) costs the least per 1,000 emails. Lakewave's email finder API costs nothing beyond the plan price. [StableEnrich's pay-as-you-go plan](https://datacircle.dev/find-email-apis/stableenrich/pay-as-you-go-pay-per-request-with-x402-or-mpp-post-api-minerva-enrich/llms.txt) costs the least for 10,000 emails a month: $1.00.
[ClearBounce's $4 pack](https://datacircle.dev/find-email-apis/clearbounce/4-pack/llms.txt) covers any number of emails. ClearBounce's $4 pack costs less up front than Lakewave's $19 monthly plan.
[GetProspect](https://datacircle.dev/find-email-apis/getprospect/399-monthly-growth-50k-post-v2-email-find/llms.txt), [DiscoLike](https://datacircle.dev/find-email-apis/discolike/399-monthly-team-post-email-find/llms.txt) and [Icypeas](https://datacircle.dev/find-email-apis/icypeas/499-monthly-hypergrowth-100000-credits-a-month-post-email-search/llms.txt) are the best email finder API providers in the Datacircle benchmark.

- This page: https://datacircle.dev/find-email-apis/leadbase/free
- [Email finder API in 2026: the best of 100+ compared](https://datacircle.dev/best-email-finder-api.txt)
- Get it: https://www.leadbase.io/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-finder-api-pricing
- Request: `POST https://www.leadbase.io/api/v1/operations/prospects.find_email`
- API key: with the plan, on https://www.leadbase.io/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-finder-api-pricing
- Its API docs: https://www.leadbase.io/docs/enrichment/contact-data?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-finder-api-pricing
- Sold by: Leadbase (https://www.leadbase.io?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-finder-api-pricing)
- Checked: 2026-11-10

## In the answer

- Completeness: 0%

## Price

- $ per 1,000 emails: $0.00
- Per: call
- Billing: free

## Aggregators

- Aggregators: none

## Overage

- Units cap: hard

## Not found

- $ per 1,000 calls that find nothing: $0.00

## In their words

- Their pitch: Find work email addresses and direct phone numbers using an identifiable professional profile.

## Data

- Keep data: no limit
- Use data: Leadbase grants the customer a non-exclusive, non-transferable, revocable right of use for the services and provided data for the term of the contract. This right is limited to the agreed use and the booked service level. Permitted use: Lead generation and prospecting for own business purposes, CRM data enrichment for existing customer databases, Sales and marketing activities in the B2B area, Integration into own business processes and software tools, Forwarding enriched data to employees and authorized service providers. Prohibited use: Resale, rental or commercial transfer of data to third parties, Reverse engineering, decompilation or replication of the platform, Automated mass queries outside the API limits, Use for spam, unwanted advertising or harassment, Data breaches or breaches of opt-out requests, Use for illegal, harmful or discriminatory purposes, Creation of competing products or services. Absolutely prohibited use: Spam, unwanted mass advertising or cold email campaigns without legal basis, Sale, rental or other commercial transfer of data, Use for credit checks, background checks or other SCHUFA-like purposes, Discrimination based on sex, race, religion or other characteristics, Stalking, harassment or other unlawful contact, Generating fake identities or fake company profiles, Use for political campaigns without corresponding licensing, Breach of embargoes or trade restrictions.

## Plan

- Pay: €0
- You get: 200 credits
- Enough for: 200 calls, once
- Expires: never

## Rate limit

- Per second: 10
- Batch: 1

## Speed

- Answer: in the call

## The call

- You send: idempotencyKey, identity.kind "linkedin" or "person_at_company", identity.linkedinUrl, identity.firstName, identity.lastName, identity.companyDomain. Optional: identity.companyName, identity.countryCode, identity.jobTitle
- Method: POST
- Path: /api/v1/operations/prospects.find_email

## About the plan

- Plan: Free
- Who can get it: business customers only ("Leadbase is intended exclusively for business customers (B2B)")

## The 9 fields the plan's answer can hold

email, status, group ID, eligible options, compatible options, skipped options, attempts, presence decision, cost in micro-USD

## Leadbase's plans (4)

- [Leadbase, free](https://datacircle.dev/find-email-apis/leadbase/free/llms.txt): $0.00 per 1,000, 0% complete
- [Leadbase, €390 monthly](https://datacircle.dev/find-email-apis/leadbase/390-monthly/llms.txt): $90.024 per 1,000, 0% complete
- [Leadbase, €590 monthly](https://datacircle.dev/find-email-apis/leadbase/590-monthly/llms.txt): $78.109 per 1,000, 0% complete
- [Leadbase, €990 monthly](https://datacircle.dev/find-email-apis/leadbase/990-monthly/llms.txt): $67.518 per 1,000, 0% complete

## Leadbase's calls for this API (1)

- `POST /api/v1/operations/prospects.find_email`: [Leadbase, free](https://datacircle.dev/find-email-apis/leadbase/free/llms.txt)

## Leadbase's APIs (4)

- [Leadbase: company discovery API pricing, 4 plans](https://datacircle.dev/company-discovery-apis/leadbase/free/llms.txt)
- [Leadbase: email finder API pricing, 4 plans](https://datacircle.dev/find-email-apis/leadbase/free/llms.txt)
- [Leadbase: phone finder API pricing, 4 plans](https://datacircle.dev/find-phone-apis/leadbase/free/llms.txt)
- [Leadbase: people search API pricing, 4 plans](https://datacircle.dev/people-search-apis/leadbase/free/llms.txt)

## Leadbase: email finder API alternatives

- [DataVertex, $2,700 yearly](https://datacircle.dev/find-email-apis/datavertex/2700-yearly/llms.txt): $67.50 per 1,000, 50% complete, live
- [Listar, top-up from €100,000, Diamond, POST /search/unified](https://datacircle.dev/find-email-apis/listar/top-up-from-100000-diamond-post-search-unified/llms.txt): $67.518 per 1,000, 60% complete
- [Lix, $339 monthly](https://datacircle.dev/find-email-apis/lix/339-monthly/llms.txt): $67.80 per 1,000, 10% complete, live
- [Verifox, $34 pack](https://datacircle.dev/find-email-apis/verifox/34-pack/llms.txt): $68.00 per 1,000, 10% complete, live
- [Sourcing.sh, €516.35 monthly](https://datacircle.dev/find-email-apis/sourcing-sh/516-35-monthly/llms.txt): $68.359 per 1,000, 0% complete

## Sources

From each provider's own pricing page and docs, and from what providers tell us. We read this row from these pages on 2026-11-10.

- https://www.leadbase.io/api/v1/openapi.json?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-finder-api-pricing
- https://www.leadbase.io/docs/api?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-finder-api-pricing
- https://www.leadbase.io/docs/api/authentication?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-finder-api-pricing
- https://www.leadbase.io/docs/enrichment/contact-data?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-finder-api-pricing
- https://www.leadbase.io/legal/terms?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-finder-api-pricing
- https://www.leadbase.io/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-finder-api-pricing