# MailChecked, free, POST /validate: Email verification API

> MailChecked is an email validation and verification service that confirms real inbox deliverability — verify single addresses in the dashboard, clean bulk CSV lists, or integrate via REST API — without trashing your sender reputation.

MailChecked'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 MailChecked through [our email verification API benchmark](https://datacircle.dev/best-email-verification-api.txt) yet.
This plan is free. We rank 3,886 plans for email verification APIs by price. Half the plans cost $1.998 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.
[email-validation.org](https://datacircle.dev/validate-email-apis/email-validation-org/450-pack-1000000-credits-post-v1-validate/llms.txt), [pingutil](https://datacircle.dev/validate-email-apis/pingutil/free-api-key-post-v1-verify/llms.txt) and [MailTester Ninja](https://datacircle.dev/validate-email-apis/mailtester-ninja/23-99-monthly/llms.txt) are the best email verification API providers in the Datacircle benchmark.

- This page: https://datacircle.dev/validate-email-apis/mailchecked/free-post-validate
- [Email validation API: 180+ verification providers compared](https://datacircle.dev/best-email-verification-api.txt)
- Get it: https://mailchecked.com/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Request: `POST https://app.mailchecked.com/v1/validate`
- API key: with the plan, on https://mailchecked.com/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Its API docs: https://mailchecked.com/docs/?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Sold by: MailChecked (https://mailchecked.com?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing)
- Checked: 2026-11-02

## In the answer

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

## Price

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

## Aggregators

- Aggregators: none

## Charges

- Also pays for: from the same budget: POST /v1/bulk · POST /v1/bulk/csv

## Overage

- Units cap: hard

## Not found

- $ per 1,000: $0.00

## Catch-all

- $ per 1,000: $0.00

## Bounce

- Bounce refund: the credit, when a Valid result hard-bounces within 14 days, reported through the API, the dashboard or by email

## In their words

- Their pitch: MailChecked is an email validation and verification service that confirms real inbox deliverability — verify single addresses in the dashboard, clean bulk CSV lists, or integrate via REST API — without trashing your sender reputation.

## Data

- Freshness: live
- What it checks: format, mail servers, disposable domains, role addresses, mailbox
- Keep data: no limit
- Use data: You may not use MailChecked to: validate scraped or purchased lists where the data subjects have not given a lawful basis for being contacted by you, support spam, phishing, malware distribution, scams, fraud, or pyramid schemes, harass, dox, threaten, or stalk any individual, validate addresses for credential-stuffing, account-takeover, or enumeration attacks, verify lists you intend to send unsolicited bulk email to, including but not limited to CAN-SPAM, GDPR, PECR, CASL, or Australian Spam Act violations, circumvent rate limits by creating multiple accounts, masking source IPs, or otherwise evading our throttles, resell, white-label, or sublicense the service without our written consent, reverse-engineer, scrape, or attempt to extract our validation cache, scoring weights, or provider classification logic, probe, scan, or interfere with the security or integrity of MailChecked or any third-party system you encounter through our service, submit data you are legally prohibited from disclosing (sealed, classified, etc.), use the service in violation of applicable law in your jurisdiction or the recipient's. You must have a lawful basis to validate any email address you submit.

## Plan

- Pay: $0
- You get: 100 credits
- Enough for: 100 calls, once
- Expires: never

## Rate limit

- Batch: 1

## Speed

- Answer: in the call

## The call

- You send: email, Content-Type header "application/json"
- Method: POST
- Path: /validate

## About the plan

- Plan: Free
- Who can get it: anyone at least 16 years old and able to form a binding contract

## The 14 fields the plan's answer can hold

email, verdict, score, syntax check, MX check, SMTP result, catch-all, disposable, role, free provider, provider, credits charged, cached, request ID

## MailChecked's plans (6)

- [MailChecked, free, POST /validate](https://datacircle.dev/validate-email-apis/mailchecked/free-post-validate/llms.txt): $0.00 per 1,000, 50% complete, live
- [MailChecked, $5 pack, Starter, POST /validate](https://datacircle.dev/validate-email-apis/mailchecked/5-pack-starter-post-validate/llms.txt): $5.00 per 1,000, 50% complete, live
- [MailChecked, $15 pack, 10,000 credits, POST /validate](https://datacircle.dev/validate-email-apis/mailchecked/15-pack-10000-credits-post-validate/llms.txt): $1.50 per 1,000, 50% complete, live
- [MailChecked, $50 pack, 50,000 credits, POST /validate](https://datacircle.dev/validate-email-apis/mailchecked/50-pack-50000-credits-post-validate/llms.txt): $1.00 per 1,000, 50% complete, live
- [MailChecked, $175 pack, 250,000 credits, POST /validate](https://datacircle.dev/validate-email-apis/mailchecked/175-pack-250000-credits-post-validate/llms.txt): $0.70 per 1,000, 50% complete, live
- [MailChecked, $500 pack, Scale, POST /validate](https://datacircle.dev/validate-email-apis/mailchecked/500-pack-scale-post-validate/llms.txt): $0.50 per 1,000, 50% complete, live

## MailChecked's calls (3)

- `POST /bulk`: [MailChecked, free, POST /bulk](https://datacircle.dev/validate-email-apis/mailchecked/free-post-bulk/llms.txt)
- `POST /bulk/csv`: [MailChecked, free, POST /bulk/csv](https://datacircle.dev/validate-email-apis/mailchecked/free-post-bulk-csv/llms.txt)
- `POST /validate`: [MailChecked, free, POST /validate](https://datacircle.dev/validate-email-apis/mailchecked/free-post-validate/llms.txt)

## MailChecked's APIs (1)

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

## MailChecked: email verification API alternatives

- [Sealch, $25 monthly, Monthly up to 50,000 / mo, POST /api/verify](https://datacircle.dev/validate-email-apis/sealch/25-monthly-monthly-up-to-50000-mo-post-api-verify/llms.txt): $0.50 per 1,000, 17% complete, live
- [Verimail, $500 pack](https://datacircle.dev/validate-email-apis/verimail/500-pack/llms.txt): $0.50 per 1,000, 50% complete, live
- [Easy Email Verification, $1,200 monthly, Monthly subscription, 80,000 emails a day, POST /bulk/upload](https://datacircle.dev/validate-email-apis/easy-email-verification/1200-monthly-monthly-subscription-80000-emails-a-day-post-bulk-upload/llms.txt): $0.50 per 1,000, 50% complete, live
- [NullBounce, $500 pack](https://datacircle.dev/validate-email-apis/nullbounce/500-pack/llms.txt): $0.50 per 1,000, 33% 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 2026-11-02.

- https://mailchecked.com?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://mailchecked.com/api?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://mailchecked.com/docs?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://mailchecked.com/legal/aup?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://mailchecked.com/legal/refund?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://mailchecked.com/legal/terms?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://mailchecked.com/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing