# Blackwood State, pay as you go, x402 pay per call, POST /v1/email-check: Email verification API

> Returns JSON with email verification of one address: syntax, domain MX records, disposable, free and role-account flags, SPF and DMARC, and a verdict on whether the domain can receive mail.

Blackwood State's x402 pay per call plan for the email verification API costs $5.00 per 1,000 emails. We check each provider's docs for 6 fields. Blackwood State's docs list 3: Address, Deliverability, Company.
We haven't run Blackwood State through [our email verification API benchmark](https://datacircle.dev/best-email-verification-api.txt) yet.
We rank 4,337 plans for email verification APIs by price. Half the plans cost $2.00 or less per 1,000 emails. This plan costs less per 1,000 emails than 22% of the 4,337 plans.
[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. [StableEnrich's pay-as-you-go plan](https://datacircle.dev/validate-email-apis/stableenrich/pay-as-you-go-pay-per-request-with-x402-or-mpp-post-api-minerva-validate-emails/llms.txt) costs the least for 10,000 emails a month: $0.05.
[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.
[pingutil](https://datacircle.dev/validate-email-apis/pingutil/free-api-key-post-v1-verify/llms.txt), [Validemail.co](https://datacircle.dev/validate-email-apis/validemail-co/9-90-monthly-9-90-month-get-api-v1-validate/llms.txt) and [looot](https://datacircle.dev/validate-email-apis/looot/top-up/llms.txt) are the best email verification API providers in the Datacircle benchmark.

- This page: https://datacircle.dev/validate-email-apis/blackwood-state/pay-as-you-go-x402-pay-per-call-post-v1-email-check
- [Email validation API: best verification providers compared](https://datacircle.dev/best-email-verification-api.txt)
- Get it: https://x402-gateway.blackwoodstate8.workers.dev?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Request: `POST https://x402-gateway.blackwoodstate8.workers.dev/v1/email-check`
- API key: not needed
- Its API docs: https://x402-gateway.blackwoodstate8.workers.dev/services/email-check?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Sold by: Blackwood State (https://x402-gateway.blackwoodstate8.workers.dev?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing)
- Checked: 2026-11-09

## In the answer

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

## Price

- $ per 1,000 emails: $5.00
- Per: call
- Billing: pay as you go

## Aggregators

- Aggregators: none

## Charges

- Also pays for: nothing else

## In their words

- Their pitch: Returns JSON with email verification of one address: syntax, domain MX records, disposable, free and role-account flags, SPF and DMARC, and a verdict on whether the domain can receive mail.

## Data

- What it checks: format, mail servers, disposable domains, role addresses
- Keep data: no API terms
- Use data: no API terms

## Plan

- Pay: per call

## Rate limit

- Batch: 1

## Speed

- Answer: in the call

## The call

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

## About the plan

- Plan: x402 pay per call
- Who can get it: anyone with a wallet paying each call in USDC on Base (x402), with no account or API key

## The 16 fields the plan's answer can hold

email, normalized email, syntax valid, domain, disposable, free provider, role account, domain exists, MX records, accepts mail, SPF record, DMARC record, DMARC policy, verdict, reasons, SMTP checked

## Blackwood State's plans (4)

- [Blackwood State, pay as you go, x402 pay per call, POST /v1/email-check](https://datacircle.dev/validate-email-apis/blackwood-state/pay-as-you-go-x402-pay-per-call-post-v1-email-check/llms.txt): $5.00 per 1,000, 50% complete
- [Blackwood State, $5 pack, Prepaid credits, $5 pack, POST /v1/email-check](https://datacircle.dev/validate-email-apis/blackwood-state/5-pack-prepaid-credits-5-pack-post-v1-email-check/llms.txt): $5.00 per 1,000, 50% complete
- [Blackwood State, $20 pack, Prepaid credits, $20 pack, POST /v1/email-check](https://datacircle.dev/validate-email-apis/blackwood-state/20-pack-prepaid-credits-20-pack-post-v1-email-check/llms.txt): $4.50 per 1,000, 50% complete
- [Blackwood State, $100 pack, Prepaid credits, $100 pack, POST /v1/email-check](https://datacircle.dev/validate-email-apis/blackwood-state/100-pack-prepaid-credits-100-pack-post-v1-email-check/llms.txt): $4.00 per 1,000, 50% complete

## Blackwood State's calls for this API (2)

- `POST /v1/email-batch`: [Blackwood State, pay as you go, x402 pay per call, POST /v1/email-batch](https://datacircle.dev/validate-email-apis/blackwood-state/pay-as-you-go-x402-pay-per-call-post-v1-email-batch/llms.txt)
- `POST /v1/email-check`: [Blackwood State, pay as you go, x402 pay per call, POST /v1/email-check](https://datacircle.dev/validate-email-apis/blackwood-state/pay-as-you-go-x402-pay-per-call-post-v1-email-check/llms.txt)

## Blackwood State's APIs (4)

- [Blackwood State: domain WHOIS API pricing, 4 plans](https://datacircle.dev/domain-whois-apis/blackwood-state/pay-as-you-go/llms.txt)
- [Blackwood State: news API pricing, 4 plans](https://datacircle.dev/news-apis/blackwood-state/pay-as-you-go/llms.txt)
- [Blackwood State: web scraping API pricing, 4 plans](https://datacircle.dev/web-scraping-apis/blackwood-state/pay-as-you-go/llms.txt)
- [Blackwood State: email verification API pricing, 4 plans, POST /v1/email-check](https://datacircle.dev/validate-email-apis/blackwood-state/pay-as-you-go-x402-pay-per-call-post-v1-email-check/llms.txt)

## Blackwood State: email verification API alternatives

- [MillionPhones, top-up from $5](https://datacircle.dev/validate-email-apis/millionphones/top-up-from-5/llms.txt): $5.00 per 1,000, 33% complete, live
- [NullBounce, $5 pack](https://datacircle.dev/validate-email-apis/nullbounce/5-pack/llms.txt): $5.00 per 1,000, 33% complete, live
- [Qualisend, $5 monthly, Pro, 1,000 credits a month, POST /verify/bulk](https://datacircle.dev/validate-email-apis/qualisend/5-monthly-pro-1000-credits-a-month-post-verify-bulk/llms.txt): $5.00 per 1,000, 50% complete, live
- [MailProbe, $5 pack](https://datacircle.dev/validate-email-apis/mailprobe/5-pack/llms.txt): $5.00 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 2026-11-09.

- https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://x402-gateway.blackwoodstate8.workers.dev?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://x402-gateway.blackwoodstate8.workers.dev/llms.txt?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://x402-gateway.blackwoodstate8.workers.dev/openapi.json?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://x402-gateway.blackwoodstate8.workers.dev/services/email-check?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing