# Unspam, $5 monthly, Custom plan, first 1,000 verifications a month, POST /email-verification/instant-checks: Email verification API

> Verify one address or a list of up to 100,000 over REST, and read back a status, a reason and an action for each, paying only for definitive answers.

Unspam's "Custom plan, first 1,000 verifications a month" for the email verification API costs $6.40 per 1,000 emails. Unspam's docs list 3 of the 6 fields on our checklist: Address, Deliverability, Company.
We haven't run Unspam through [our email verification API benchmark](https://datacircle.dev/best-email-verification-api.txt) yet.
Half of the 4,041 plans we rank by price cost $1.999 per 1,000 emails or less. This plan costs less per 1,000 emails than 17% of the 4,041 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), [looot](https://datacircle.dev/validate-email-apis/looot/top-up/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/unspam/5-monthly-custom-plan-first-1000-verifications-a-month-post-email-verification-instant-checks
- [Email validation API: 210+ verification providers compared](https://datacircle.dev/best-email-verification-api.txt)
- Get it: https://unspam.email/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Request: `POST https://api.unspam.email/ext/v2/email-verification/instant-checks`
- API key: with the plan, on https://unspam.email/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Its API docs: https://unspam.email/email-verification-api?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Sold by: Unspam (https://unspam.email?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing)
- Checked: 2026-11-07

## In the answer

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

## Price

- $ per 1,000 emails: $6.40
- Per: call
- Billing: monthly
- $ a month: $5

## Aggregators

- Aggregators: none

## Charges

- Also pays for: from the same budget: Verify email list

## Overage

- Add-ons: 1,000 credits once for $8 ($8.00 per 1,000)

## Not found

- $ per 1,000: $0.00

## Catch-all

- $ per 1,000: $6.40

## In their words

- Their pitch: Verify one address or a list of up to 100,000 over REST, and read back a status, a reason and an action for each, paying only for definitive answers.

## Data

- Freshness: live
- What it checks: format, mail servers, disposable domains, role addresses, mailbox
- Keep data: no limit
- Use data: If you are on the Custom plan, or on a White Label plan we issued to you, you may integrate the Service, including the API and the MCP server, into your own products and services, and you may offer and resell the results to your own clients under your own brand, without attribution to Unspam. You remain responsible for how your clients use the results and for their compliance with these Terms, and you must keep your API tokens confidential.

## Plan

- Pay: $5
- You get: from the 1st call a month
- Expires: the monthly allowance resets on the billing anniversary

## Rate limit

- Per second: 1.67
- Batch: 1

## Speed

- Answer: by polling

## The call

- You send: email
- Method: POST
- Path: /email-verification/instant-checks

## About the plan

- Plan: Custom plan, first 1,000 verifications a month
- Who can get it: anyone above the age of 18

## The 23 fields the plan's answer can hold

ID, email address, check status, status, reason, action, flags, did you mean, domain, mail provider, MX records, MX accepts mail, SMTP connected, mailbox accepts, catch-all, full inbox, disabled, disposable, role, free provider, charged, created at, completed at

## Unspam's plans (8)

- [Unspam, $5 monthly, Custom plan, first 1,000 verifications a month, POST /email-verification/instant-checks](https://datacircle.dev/validate-email-apis/unspam/5-monthly-custom-plan-first-1000-verifications-a-month-post-email-verification-instant-checks/llms.txt): $6.40 per 1,000, 50% complete, live
- [Unspam, $6.40 monthly, Custom plan, next 9,000 verifications a month, POST /email-verification/instant-checks](https://datacircle.dev/validate-email-apis/unspam/0-monthly-custom-plan-next-9000-verifications-a-month-post-email-verification-instant-checks/llms.txt): $4.00 per 1,000, 50% complete, live
- [Unspam, $42.40 monthly, Custom plan, next 90,000 verifications a month, POST /email-verification/instant-checks](https://datacircle.dev/validate-email-apis/unspam/36-monthly-custom-plan-next-90000-verifications-a-month-post-email-verification-instant-checks/llms.txt): $2.40 per 1,000, 50% complete, live
- [Unspam, $258.40 monthly, Custom plan, over 100,000 verifications a month, POST /email-verification/instant-checks](https://datacircle.dev/validate-email-apis/unspam/252-monthly-custom-plan-over-100000-verifications-a-month-post-email-verification-instant-checks/llms.txt): $1.20 per 1,000, 50% complete, live
- [Unspam, $51 yearly, Custom plan, annual billing, first 1,000 verifications a month, POST /email-verification/instant-checks](https://datacircle.dev/validate-email-apis/unspam/51-yearly-custom-plan-annual-billing-first-1000-verifications-a-month-post-email-verification-instant-checks/llms.txt): $5.44 per 1,000, 50% complete, live
- [Unspam, $65.28 yearly, Custom plan, annual billing, next 9,000 verifications a month, POST /email-verification/instant-checks](https://datacircle.dev/validate-email-apis/unspam/0-yearly-custom-plan-annual-billing-next-9000-verifications-a-month-post-email-verification-instant-checks/llms.txt): $3.40 per 1,000, 50% complete, live
- [Unspam, $432.48 yearly, Custom plan, annual billing, next 90,000 verifications a month, POST /email-verification/instant-checks](https://datacircle.dev/validate-email-apis/unspam/30-60-yearly-custom-plan-annual-billing-next-90000-verifications-a-month-post-email-verification-instant-checks/llms.txt): $2.04 per 1,000, 50% complete, live
- [Unspam, $2,635.68 yearly, Custom plan, annual billing, over 100,000 verifications a month, POST /email-verification/instant-checks](https://datacircle.dev/validate-email-apis/unspam/214-20-yearly-custom-plan-annual-billing-over-100000-verifications-a-month-post-email-verification-instant-checks/llms.txt): $1.02 per 1,000, 50% complete, live

## Unspam's calls (2)

- `POST /email-verification/instant-checks`: [Unspam, $5 monthly, Custom plan, first 1,000 verifications a month, POST /email-verification/instant-checks](https://datacircle.dev/validate-email-apis/unspam/5-monthly-custom-plan-first-1000-verifications-a-month-post-email-verification-instant-checks/llms.txt)
- `POST /email-verification/list-checks`: [Unspam, $5 monthly, Custom plan, first 1,000 verifications a month, POST /email-verification/list-checks](https://datacircle.dev/validate-email-apis/unspam/5-monthly-custom-plan-first-1000-verifications-a-month-post-email-verification-list-checks/llms.txt)

## Unspam's APIs (1)

- [Unspam: email verification API pricing, 8 plans, POST /email-verification/instant-checks](https://datacircle.dev/validate-email-apis/unspam/5-monthly-custom-plan-first-1000-verifications-a-month-post-email-verification-instant-checks/llms.txt)

## Unspam: email verification API alternatives

- [Anymail Finder, $384 yearly](https://datacircle.dev/validate-email-apis/anymail-finder/384-yearly/llms.txt): $6.40 per 1,000, 17% complete, live
- [SafetyMails, $12.80 monthly](https://datacircle.dev/validate-email-apis/safetymails/12-80-monthly/llms.txt): $6.40 per 1,000, 33% complete, live
- [Gamalogic, $16 pack, Pay As You Go, 2,500 Credits, POST /batchemailvrf](https://datacircle.dev/validate-email-apis/gamalogic/16-pack-pay-as-you-go-2500-credits-post-batchemailvrf/llms.txt): $6.40 per 1,000, 17% complete, live
- [Oppora, $96 quarterly, Pro, POST /email/verify, Verify email (advanced mode)](https://datacircle.dev/validate-email-apis/oppora/96-quarterly-pro-post-email-verify-verify-email-advanced-mode/llms.txt): $6.40 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 2026-11-07.

- https://api.unspam.email/ext-api/openapi.json?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://unspam.email/api?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://unspam.email/api/internal/custom-plan/config?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://unspam.email/email-verification-api?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://unspam.email/email-verifier?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://unspam.email/pricing?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://unspam.email/privacy?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://unspam.email/terms?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing