# ContactLint, free, POST /v1/email/validate: Email verification API

> Catch typos like gmial.com, throwaway inboxes and dead domains the moment someone signs up, or right before your agent saves a contact. One HTTP call or one MCP tool call.

ContactLint'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, Company.
We rank 2,467 plans by price. [treg's top-up from $10](https://datacircle.dev/validate-email-apis/treg/top-up-from-10/llms.txt) costs the least per 1,000 emails: $0.00 on average. treg asks one provider after another until one answers. You pay $26.95 per 1,000 emails when no provider answers.
[Enrich.so](https://datacircle.dev/validate-email-apis/enrich-so/149-monthly/llms.txt), [GetProspect](https://datacircle.dev/validate-email-apis/getprospect/369-pack/llms.txt) and [treg](https://datacircle.dev/validate-email-apis/treg/top-up-from-10/llms.txt) are the best email verification API providers in our benchmark.

- This page: https://datacircle.dev/validate-email-apis/contactlint/free-post-v1-email-validate
- [Best email verification API in 2026](https://datacircle.dev/best-email-verification-api.txt)
- Get it: https://contactlint.com/email-validation-api-pricing
- Request: `POST https://contactlint.com/v1/email/validate`
- API key: with the plan, on https://contactlint.com/email-validation-api-pricing
- Its API docs: https://contactlint.com/docs
- Sold by: ContactLint (https://contactlint.com)
- Checked: 2026-10-27

## In the answer

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

## Price

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

## Aggregators

- Aggregators: none

## Charges

- Also pays for: from the same budget: Validate up to 50 emails in one request · Validate one phone

## Not found

- $ per 1,000: $0.00

## Catch-all

- $ per 1,000: $0.00

## In their words

- Their pitch: Catch typos like gmial.com, throwaway inboxes and dead domains the moment someone signs up, or right before your agent saves a contact. One HTTP call or one MCP tool call.

## Data

- Freshness: stored
- What it checks: format, mail servers, disposable domains, role addresses
- Keep data: no limit
- Use data: You own the data you send us and the results we return to you. [...] You agree not to: Use the Service to build lists for spam, or to check addresses or numbers you have no lawful reason to process. Try to get around rate limits, free-tier limits or signup limits (for example by creating many keys). Probe, overload or attack the Service, or resell raw access to the API without our written OK. Send data you are not allowed to share, such as sensitive data unrelated to contact validation. You are responsible for complying with laws that apply to you, including anti-spam, telemarketing, and data protection laws, when you use the results.

## Plan

- Pay: $0
- You get: 100 credits a month
- Enough for: 100 calls a month
- Expires: unused free checks do not roll over

## Rate limit

- Per second: 1
- Batch: 1

## Speed

- Answer: in the call

## The call

- You send: email
- Method: POST
- Path: /v1/email/validate

## About the plan

- Plan: Free
- Who can get it: anyone with a non-disposable email address

## The 17 fields the plan's answer can hold

email address, syntax valid, reason, domain, disposable, role address, did you mean, free provider, MX found, A record found, MX records, deliverable domain, verdict, billed as, free checks used this month, free check limit, credits remaining

## ContactLint's plans (4)

- [ContactLint, free, POST /v1/email/validate](https://datacircle.dev/validate-email-apis/contactlint/free-post-v1-email-validate/llms.txt): $0.00 per 1,000, 50% complete, stored
- [ContactLint, $9 pack, Credit pack 5,000, POST /v1/email/validate](https://datacircle.dev/validate-email-apis/contactlint/9-pack-credit-pack-5000-post-v1-email-validate/llms.txt): $1.80 per 1,000, 50% complete, stored
- [ContactLint, $35 pack, Credit pack 25,000, POST /v1/email/validate](https://datacircle.dev/validate-email-apis/contactlint/35-pack-credit-pack-25000-post-v1-email-validate/llms.txt): $1.40 per 1,000, 50% complete, stored
- [ContactLint, $99 pack, Credit pack 100,000, POST /v1/email/validate](https://datacircle.dev/validate-email-apis/contactlint/99-pack-credit-pack-100000-post-v1-email-validate/llms.txt): $0.99 per 1,000, 50% complete, stored

## ContactLint's calls for this API (2)

- `POST /v1/email/validate`: [ContactLint, free, POST /v1/email/validate](https://datacircle.dev/validate-email-apis/contactlint/free-post-v1-email-validate/llms.txt)
- `POST /v1/email/validate/batch`: [ContactLint, free, POST /v1/email/validate/batch](https://datacircle.dev/validate-email-apis/contactlint/free-post-v1-email-validate-batch/llms.txt)

## ContactLint's APIs (2)

- [ContactLint: phone validation API pricing, 4 plans](https://datacircle.dev/validate-phone-apis/contactlint/free/llms.txt)
- [ContactLint: email verification API pricing, 4 plans, POST /v1/email/validate](https://datacircle.dev/validate-email-apis/contactlint/free-post-v1-email-validate/llms.txt)

## ContactLint: email verification API alternatives

- [KaijuVerifier, $49 monthly, Growth, POST /api/v1/verify-single, Verify a single email (authenticated)](https://datacircle.dev/validate-email-apis/kaijuverifier/49-monthly-growth-post-api-v1-verify-single-verify-a-single-email-authenticated/llms.txt): $0.98 per 1,000, 50% complete, stored (DNS valid, MX count, MX providers, MX grade: live)
- [Elastic Email, $49 monthly, Email API Pro (50,000 emails/month), POST /verifications/{email}](https://datacircle.dev/validate-email-apis/elastic-email/49-monthly-email-api-pro-50000-emails-month-post-verifications-email/llms.txt): $0.98 per 1,000, 50% complete, stored
- [BigDataCloud, $9.95 monthly](https://datacircle.dev/validate-email-apis/bigdatacloud/9-95-monthly/llms.txt): $0.995 per 1,000, 33% complete, stored
- [Emailit, top-up from $20, Pay as you go, POST /email-verifications, Verify an address](https://datacircle.dev/validate-email-apis/emailit/top-up-from-20-pay-as-you-go-post-email-verifications-verify-an-address/llms.txt): $1.00 per 1,000, 67% complete, stored (has MX records: 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 2026-10-27.

- https://contactlint.com
- https://contactlint.com/docs
- https://contactlint.com/email-validation-api-pricing
- https://contactlint.com/openapi.json
- https://contactlint.com/privacy
- https://contactlint.com/terms