# ListCheckup, free, POST /v1/lists: Email verification API

> Check one address, or a list of any size, from your own code. Same credits as the dashboard, same verdicts.

ListCheckup's email verification API on its Free plan. It costs $0.00 per 1,000 emails. It returns 3 of the 6 key fields we check: Address, Deliverability, Confidence.
We haven't run ListCheckup through [our email verification API benchmark](https://datacircle.dev/best-email-verification-api.txt) yet.
This plan is free. We rank 3,753 plans for email verification APIs by price. Half the plans cost $1.98 per 1,000 emails or less.
[treg's top-up from $10](https://datacircle.dev/validate-email-apis/treg/top-up-from-10/llms.txt) is the cheapest paid plan per 1,000 emails: $0.00 on average. treg asks one provider after another until one answers. You pay $68.365 per 1,000 emails when no provider answers.
[Disify's $9 monthly plan (/email)](https://datacircle.dev/validate-email-apis/disify/9-monthly-starter-post-email/llms.txt) covers any number of emails. Disify's $9 monthly plan costs less up front than treg's top-up from $10.
[MailTester Ninja](https://datacircle.dev/validate-email-apis/mailtester-ninja/23-99-monthly/llms.txt), [Enrich.so](https://datacircle.dev/validate-email-apis/enrich-so/499-monthly/llms.txt) and [GetProspect](https://datacircle.dev/validate-email-apis/getprospect/369-pack/llms.txt) are the best email verification API providers in the Datacircle benchmark.

- This page: https://datacircle.dev/validate-email-apis/listcheckup/free-post-v1-lists
- [Email validation API: 180+ verification providers compared](https://datacircle.dev/best-email-verification-api.txt)
- Get it: https://listcheckup.com/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Request: `POST https://listcheckup.com/v1/lists`
- API key: with the plan, on https://listcheckup.com/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Its API docs: https://listcheckup.com/api?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Sold by: ListCheckup (https://listcheckup.com?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing)
- Checked: 2026-11-05

## In the answer

- Completeness: 50%
- Address: ✓
- Deliverability: ✓
- Confidence: ✓

## Price

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

## Aggregators

- Aggregators: none

## Charges

- Also pays for: from the same budget: Verify one address

## Overage

- Units cap: hard

## Not found

- $ per 1,000: $0.00

## In their words

- Their pitch: Check one address, or a list of any size, from your own code. Same credits as the dashboard, same verdicts.

## Data

- Freshness: live
- What it checks: format, mail servers, disposable domains, role addresses, mailbox
- Keep data: no limit
- Use data: You may not use the Service to: verify addresses you obtained without a lawful basis, including scraped or purchased lists you have no right to process, support the sending of unsolicited bulk email, or any activity that violates anti-spam law in the recipient's jurisdiction, enumerate, guess, or harvest addresses, including submitting generated permutations of a domain's addresses, circumvent credit limits, rate limits, or authentication, or resell the Service without a written agreement, interfere with the Service or attempt to gain unauthorised access to it.

## Plan

- Pay: $0
- You get: 100 credits a month
- Enough for: 100 results a month
- Expires: never

## Rate limit

- Per second: 1
- Batch: no limit

## Speed

- Answer: by polling or webhook

## The call

- You send: name, emails
- Method: POST
- Path: /v1/lists

## About the plan

- Plan: Free
- Who can get it: anyone

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

list ID, total results, row, email address, status, reason, confidence score, billable, duplicate of row

## ListCheckup's plans (6)

- [ListCheckup, free, POST /v1/lists](https://datacircle.dev/validate-email-apis/listcheckup/free-post-v1-lists/llms.txt): $0.00 per 1,000, 50% complete, live
- [ListCheckup, €5 pack, Trial, POST /v1/lists](https://datacircle.dev/validate-email-apis/listcheckup/5-pack-trial-post-v1-lists/llms.txt): $5.627 per 1,000, 50% complete, live
- [ListCheckup, €19 pack, Starter, POST /v1/lists](https://datacircle.dev/validate-email-apis/listcheckup/19-pack-starter-post-v1-lists/llms.txt): $4.276 per 1,000, 50% complete, live
- [ListCheckup, €55 pack, Growth, POST /v1/lists](https://datacircle.dev/validate-email-apis/listcheckup/55-pack-growth-post-v1-lists/llms.txt): $2.476 per 1,000, 50% complete, live
- [ListCheckup, €149 pack, Scale, POST /v1/lists](https://datacircle.dev/validate-email-apis/listcheckup/149-pack-scale-post-v1-lists/llms.txt): $1.677 per 1,000, 50% complete, live
- [ListCheckup, contact us, More than 100,000, POST /v1/lists](https://datacircle.dev/validate-email-apis/listcheckup/contact-us-more-than-100000-post-v1-lists/llms.txt): 50% complete, live

## ListCheckup's calls (2)

- `POST /v1/lists`: [ListCheckup, free, POST /v1/lists](https://datacircle.dev/validate-email-apis/listcheckup/free-post-v1-lists/llms.txt)
- `GET /v1/verify`: [ListCheckup, free, GET /v1/verify](https://datacircle.dev/validate-email-apis/listcheckup/free-get-v1-verify/llms.txt)

## ListCheckup's APIs (1)

- [ListCheckup: email verification API pricing, 6 plans, POST /v1/lists](https://datacircle.dev/validate-email-apis/listcheckup/free-post-v1-lists/llms.txt)

## ListCheckup: email verification API alternatives

- [WhoisXML API, $2,999 monthly](https://datacircle.dev/validate-email-apis/whoisxml-api/2999-monthly/llms.txt): $1.674 per 1,000, 50% complete, live
- [Enrow, $6,444 yearly, Scale, POST /email/verify/bulk](https://datacircle.dev/validate-email-apis/enrow/6444-yearly-scale-post-email-verify-bulk/llms.txt): $1.678 per 1,000, 33% complete, live
- [EmailMarker, $84 pack, 50,000 credits, POST /api/upload](https://datacircle.dev/validate-email-apis/emailmarker/84-pack-50000-credits-post-api-upload/llms.txt): $1.68 per 1,000, 17% complete, live
- [EmailListVerify, $168 monthly, 100,000 credits, POST /api/verifyApiFile](https://datacircle.dev/validate-email-apis/emaillistverify/168-monthly-100000-credits-post-api-verifyapifile/llms.txt): $1.68 per 1,000, 50% 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 2026-11-05.

- https://listcheckup.com?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://listcheckup.com/api?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://listcheckup.com/features?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://listcheckup.com/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://listcheckup.com/terms?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing