# Openapi.com, top-up, Single request, POST /email-start/{email}: Email verification API

> The Email Verification Start service allows you to check the validity and characteristics of an email address in just a few seconds and on a global scale

Openapi.com's email verification API on its Single request plan. It costs $3.376 per 1,000 emails. It returns 2 of the 6 key fields we check: Address, Deliverability.
€3.00 per 1,000 is $3.376, at the European Central Bank's $1.1253 for €1.
Half of the 1,712 plans we rank by price cost $2.632 per 1,000 or less. This plan costs less than 41% of the 1,712 plans.
The cheapest plan we rank by price is [treg, top-up from $10](https://datacircle.dev/validate-email-apis/treg/top-up-from-10/llms.txt), at $0.00 per 1,000.

- This page: https://datacircle.dev/validate-email-apis/openapi-com/top-up-single-request-post-email-start-email
- [Best email verification API in 2026](https://datacircle.dev/best-email-verification-api.txt)
- Get it: https://openapi.com/pricing
- Its API docs: https://console.openapi.com/apis/trust/documentation#scope=POST:trust.openapi.com/email-start
- Sold by: Openapi.com (https://openapi.com)
- Checked: 2026-10-25

## In the answer

- Completeness: 33%
- Address: ✓
- Deliverability: ✓

## Price

- $ per 1,000: $3.376
- Billing: pay first

## Aggregators

- Aggregators: none

## Charges

- Per: call
- Also pays for: from the same budget: API Services

## In their words

- Their pitch: The Email Verification Start service allows you to check the validity and characteristics of an email address in just a few seconds and on a global scale

## Data

- Freshness: live
- Keep data: no limit
- Use data: The data and information provided by Openapi are for the exclusive use of the Customer, who is prohibited from copying, reproducing, assigning to third parties on any grounds and/or using them for purposes other than those expressly established in the Agreement, unless expressly authorised by Openapi and subject to the Customer undertaking to comply with the instructions provided. In particular, to obtain such authorisation, the Customer must provide Openapi with assurances: (i) that it has informed its customers that the data they provide will be transmitted to third parties for the provision of the requested service, (ii) that it has adopted an adequate privacy policy and processes its customers’ data according to security and confidentiality standards no lower than those offered by Openapi’s Privacy Policy, (iii) that it adopts all measures required by applicable law or otherwise suitable to preserve the confidentiality and security of the data provided by its customers. [...] The Customer is also prohibited from: [...] (v) using the APIs and/or the Services for purposes or in a manner that causes damage to Openapi, the Suppliers or third parties and/or violates any provision of law [...]

## Plan

- Expires: 12 months after the last top-up

## Rate limit

- Per second: 166.67
- Batch: 1

## Speed

- Answer: in the call or by polling

## The call

- You send: email. Optional: callback
- Method: POST
- Path: /email-start/{email}

## About the plan

- Plan: Single request
- Who can get it: anyone acting in the course of their business, entrepreneurial or professional activity

## The 20 fields the plan's answer can hold

request ID, email, status, SPF valid, DMARC valid, SPF details, DMARC details, free provider, disposable, catch-all, antispam, mailbox full, suggested domain, role address, IP address verification, request state, created at, updated at, message, success

## Openapi.com's plans (16)

- [Openapi.com, top-up, Single request, POST /email-start/{email}](https://datacircle.dev/validate-email-apis/openapi-com/top-up-single-request-post-email-start-email/llms.txt): $3.376 per 1,000, 33% complete, live
- [Openapi.com, €45 monthly](https://datacircle.dev/validate-email-apis/openapi-com/45-monthly/llms.txt): $50.639 per 1,000, 67% complete
- [Openapi.com, €190 monthly](https://datacircle.dev/validate-email-apis/openapi-com/190-monthly/llms.txt): $42.761 per 1,000, 67% complete
- [Openapi.com, €290 monthly](https://datacircle.dev/validate-email-apis/openapi-com/290-monthly/llms.txt): $54.39 per 1,000, 67% complete
- [Openapi.com, €500 monthly](https://datacircle.dev/validate-email-apis/openapi-com/500-monthly/llms.txt): $28.133 per 1,000, 67% complete
- [Openapi.com, €950 monthly](https://datacircle.dev/validate-email-apis/openapi-com/950-monthly/llms.txt): $21.381 per 1,000, 67% complete
- [Openapi.com, €250 yearly](https://datacircle.dev/validate-email-apis/openapi-com/250-yearly/llms.txt): $2.813 per 1,000, 33% complete, live
- [Openapi.com, €504 yearly](https://datacircle.dev/validate-email-apis/openapi-com/504-yearly/llms.txt): $47.263 per 1,000, 67% complete
- [Openapi.com, €1,150 yearly](https://datacircle.dev/validate-email-apis/openapi-com/1150-yearly/llms.txt): $2.588 per 1,000, 33% complete, live
- [Openapi.com, €2,000 yearly](https://datacircle.dev/validate-email-apis/openapi-com/2000-yearly/llms.txt): $2.251 per 1,000, 33% complete, live
- [Openapi.com, €2,040 yearly](https://datacircle.dev/validate-email-apis/openapi-com/2040-yearly/llms.txt): $38.26 per 1,000, 67% complete
- [Openapi.com, €3,120 yearly](https://datacircle.dev/validate-email-apis/openapi-com/3120-yearly/llms.txt): $48.763 per 1,000, 67% complete
- [Openapi.com, €5,000 yearly](https://datacircle.dev/validate-email-apis/openapi-com/5000-yearly/llms.txt): $1.125 per 1,000, 33% complete, live
- [Openapi.com, €6,000 yearly](https://datacircle.dev/validate-email-apis/openapi-com/6000-yearly/llms.txt): $28.133 per 1,000, 67% complete
- [Openapi.com, €8,000 yearly](https://datacircle.dev/validate-email-apis/openapi-com/8000-yearly/llms.txt): $0.90 per 1,000, 33% complete, live
- [Openapi.com, €11,400 yearly](https://datacircle.dev/validate-email-apis/openapi-com/11400-yearly/llms.txt): $21.381 per 1,000, 67% complete

## Openapi.com's calls (2)

- `POST /email-advanced/{email}`: [Openapi.com, top-up, Single request, POST /email-advanced/{email}](https://datacircle.dev/validate-email-apis/openapi-com/top-up-single-request-post-email-advanced-email/llms.txt)
- `POST /email-start/{email}`: [Openapi.com, top-up, Single request, POST /email-start/{email}](https://datacircle.dev/validate-email-apis/openapi-com/top-up-single-request-post-email-start-email/llms.txt)

## Openapi.com's APIs (2)

- [Openapi.com: email verification API pricing, 16 plans, POST /email-start/{email}](https://datacircle.dev/validate-email-apis/openapi-com/top-up-single-request-post-email-start-email/llms.txt)
- [Openapi.com: phone validation API pricing, 16 plans, POST /mobile-advanced/{mobile-phone-number}](https://datacircle.dev/validate-phone-apis/openapi-com/top-up-single-request-post-mobile-advanced-mobile-phone-number/llms.txt)
- [Openapi.com: phone validation API pricing, 16 plans, POST /phone-advanced/{phone-number}](https://datacircle.dev/validate-phone-apis/openapi-com/top-up-single-request-post-phone-advanced-phone-number/llms.txt)
- [Openapi.com: phone validation API pricing, 16 plans, POST /mobile-start/{mobile-phone-number}](https://datacircle.dev/validate-phone-apis/openapi-com/top-up-single-request-post-mobile-start-mobile-phone-number/llms.txt)

## Openapi.com: email verification API alternatives

- [Captain Verify, €75 pack, 25,000 Email Verifications, on demand, GET /verify](https://datacircle.dev/validate-email-apis/captain-verify/75-pack-25000-email-verifications-on-demand-get-verify/llms.txt): $3.376 per 1,000, 33% complete, live
- [ZeroBounce, $1,699 monthly, ZeroBounce ONE, 500,000 credits a month, POST /v2/validatebatch](https://datacircle.dev/validate-email-apis/zerobounce/1699-monthly-zerobounce-one-500000-credits-a-month-post-v2-validatebatch/llms.txt): $3.398 per 1,000, 83% complete, live
- [TrekMail, $17 pack, 5,000 credits, POST /verify/bulk, Create a bulk job (quick)](https://datacircle.dev/validate-email-apis/trekmail/17-pack-5000-credits-post-verify-bulk-create-a-bulk-job-quick/llms.txt): $3.40 per 1,000, 50% complete, live
- [Oppora, $34 monthly, Pro, POST /email/verify, Verify email](https://datacircle.dev/validate-email-apis/oppora/34-monthly-pro-post-email-verify-verify-email/llms.txt): $3.40 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 2026-10-25.

- https://console.openapi.com/apis/trust/documentation
- https://console.openapi.com/apis/trust/pricing
- https://legal.openapi.com/terms-and-conditions/term-and-condition-general-en.pdf
- https://openapi.com
- https://openapi.com/faq
- https://openapi.com/pricing