CheckNumber.AI pricing and alternatives: email verification API

CheckNumber.AI's site llms.txt Best email verification API in 2026

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17% complete: 1 of the 6 key fields we checkSee the 6 fields

$0.00per 1,000 emailsWe rank 2,475 plans by price. treg's top-up from $10 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, GetProspect and treg are the best email verification API providers in our benchmark.

Plan: Free trial one of CheckNumber.AI's 3 plans

Call: POST /v1/tasks CheckNumber.AI's only call for this API

POST /v1/tasksFree$0.00 per 1,000

API: Email verification API one of CheckNumber.AI's 2 APIs

About this item

Freshness. We don't know how fresh this plan's data is.
1 of the 6 key fields we check. Address.
Nothing to pay. You get 1,000 results once.
One call. You send file to POST /v1/tasks. You set task_type to "email_check". The call returns a job. You fetch the answer once the job is done.
Who can get it: anyone who contacts support. Keep data: no limit. Use data: with conditions.

CheckNumber.AI: email verification API alternatives

The table starts with CheckNumber.AI's cheapest paid plan. Next come plans from other providers with the price per 1,000 emails closest to CheckNumber.AI's.

	CheckNumber.AI, top-up from $20	Sealch, $25 monthly, Monthly up to 50,000 / mo, POST /api/verify	Verimail, $500 pack	Mailerio, $500 monthly, Monthly 1,000,000 emails, GET /v{version}/validate	NullBounce, $500 pack
$ per 1,000 emails	$0.50	$0.50	$0.50	$0.50	$0.50
Completeness	17%	17%	50%	67%	33%
Billing	pay first	monthly	pay first	monthly	pay first
Pay	$20	$25	$500	$500	$500
Enough for	as many as you pay for	50,000 calls a month	1,000,000 calls	as many as you pay for	1,000,000 calls
Freshness	unknown	live	live	live	live
Who can get it	anyone	anyone	businesses and professionals, not directed at anyone under 18	anyone, a minor needs a parent or guardian's permission	anyone

Every email verification API provider we score, ranked

Sources

From each provider's own pricing page and docs, and from what providers tell us. We read this row from these pages on 2026-10-28.

Product details

The key fields this plan's answer can hold, then each filled column in its row on the sheet.

Address
Deliverability, not in the answer
Confidence, not in the answer
Name, not in the answer
Place, not in the answer
Company, not in the answer

Price
$ per 1,000 emails	$0.00
Per	result
Billing	free

Aggregators
Aggregators	none

Not found
$ per 1,000	$0.00

In their words
Their pitch	Check whether email addresses are active and able to receive mail. Only supports Gmail, Yandex, Mail.ru, iCloud, Outlook, and Yahoo.

Data
What it checks	mailbox
Keep data	no limit
Use data	"This license is granted solely for Your internal business purposes" (3.1), "You agree not to (a) license, sublicense, sell, resell, transfer, assign, distribute, or otherwise commercially exploit or make available to any third party the Service in any way, except as expressly permitted by these Terms or an Agreement, (b) modify or make derivative works based upon the Service, (c) reverse engineer, decompile, or disassemble the Service or attempt to gain unauthorized access to the Service or its related systems or networks, or (d) use the Service for any purpose or in any manner that is unlawful (including in violation of the PDPA) or prohibited by these Terms. Furthermore, You agree that any phone numbers or associated data obtained through the Service shall not be used by You or any third party acting on Your behalf to: (i) contact any individual without their prior, express, and informed consent for such contact, in accordance with PDPA requirements, (ii) send unsolicited commercial communications (spam), bulk messages, or any messages in violation of applicable anti-spam laws (including the Singapore Spam Control Act) and the PDPA, (iii) send harassing, abusive, threatening, defamatory, obscene, or otherwise unlawful communications, or (iv) engage in any other practices that violate the privacy or data protection rights of individuals or any applicable laws or regulations, including the PDPA" (3.2)

Plan
Pay	$0
You get	1,000 results
Enough for	1,000 results, once

Rate limit
Batch	1,000,000

Speed
Answer	by polling

The call
You send	file, task_type "email_check"
Method	POST
Path	/v1/tasks

About the plan
Plan	Free trial
Who can get it	anyone who contacts support

The 2 fields the plan's answer can hold

email address, activated