# mxprobe, free: Email verification API

> One call returns send, hold or kill for an address, with the reason. Signup and credits happen by API too, so an outreach agent can provision itself.

mxprobe's email verification API on its 100 free checks plan. It costs $0.00 per 1,000 emails. It returns 2 of the 6 key fields we check: Address, Deliverability.
In [our email verification API benchmark](https://datacircle.dev/best-email-verification-api.txt), the best plan from mxprobe scores 66.2 out of 100. mxprobe ranks 14th of 181 providers.
This plan is free. We rank 3,753 plans for email verification APIs by price. Half the plans cost $1.98 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.
[MailTester Ninja](https://datacircle.dev/validate-email-apis/mailtester-ninja/23-99-monthly/llms.txt), [Enrich.so](https://datacircle.dev/validate-email-apis/enrich-so/499-monthly/llms.txt) and [GetProspect](https://datacircle.dev/validate-email-apis/getprospect/369-pack/llms.txt) are the best email verification API providers in the Datacircle benchmark.

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

## In the answer

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

## Price

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

## Aggregators

- Aggregators: none

## Charges

- Also pays for: nothing else

## Overage

- Units cap: hard

## Not found

- $ per 1,000: $0.00

## Catch-all

- $ per 1,000: $0.00

## In their words

- Their pitch: One call returns send, hold or kill for an address, with the reason. Signup and credits happen by API too, so an outreach agent can provision itself.

## Data

- Freshness: live
- What it checks: format, mail servers, mailbox
- Keep data: no API terms
- Use data: no API terms

## Plan

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

## Rate limit

- Per second: 1
- Batch: 100

## Speed

- Answer: in the call
- Median: 0.62 s

## The call

- You send: one of emails or email, Content-Type header "application/json"
- Method: POST
- Path: /v1/verify

## About the plan

- Plan: 100 free checks
- Who can get it: anyone

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

email address, action, verdict, reason, syntax, MX record, SMTP check, catch-all, send count, hold count, kill count, total addresses, credits used, credits left

## mxprobe's plans (2)

- [mxprobe, free](https://datacircle.dev/validate-email-apis/mxprobe/free/llms.txt): $0.00 per 1,000, 33% complete, live
- [mxprobe, $9 pack](https://datacircle.dev/validate-email-apis/mxprobe/9-pack/llms.txt): $0.90 per 1,000, 33% complete, live

## mxprobe's calls (1)

- `POST /v1/verify`: [mxprobe, free](https://datacircle.dev/validate-email-apis/mxprobe/free/llms.txt)

## mxprobe's APIs (1)

- [mxprobe: email verification API pricing, 2 plans](https://datacircle.dev/validate-email-apis/mxprobe/free/llms.txt)

## mxprobe: email verification API alternatives

- [BillionVerify, $45 pack, Popular, POST /verify/bulk](https://datacircle.dev/validate-email-apis/billionverify/45-pack-popular-post-verify-bulk/llms.txt): $0.90 per 1,000, 67% complete, live
- [Sealch, $9 monthly, Monthly up to 10,000 / mo, POST /api/verify](https://datacircle.dev/validate-email-apis/sealch/9-monthly-monthly-up-to-10000-mo-post-api-verify/llms.txt): $0.90 per 1,000, 17% complete, live
- [DeBounce, top-up from $450, 500K credits, GET /v1/, Single email validation](https://datacircle.dev/validate-email-apis/debounce/top-up-from-450-500k-credits-get-v1/llms.txt): $0.90 per 1,000, 50% complete, live
- [MailVeri, $9 pack, 10,000 credits, POST /verify-mail/](https://datacircle.dev/validate-email-apis/mailveri/9-pack-10000-credits-post-verify-mail/llms.txt): $0.90 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 2026-11-02.

- https://api.mxprobe.dev?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://mxprobe.dev?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://mxprobe.dev/llms.txt?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://mxprobe.dev/openapi.json?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing