# Agent Toolbox, free: Email verification API

> Check an email address: format, whether the domain exists and accepts mail (MX records), disposable providers, role accounts and free providers, with a valid / risky / invalid verdict. The mailbox itself is not probed.

Agent Toolbox's Free plan for the email verification API costs $0.00 per 1,000 emails. We check each provider's docs for 6 fields. Agent Toolbox's docs list 3: Address, Deliverability, Company.
Agent Toolbox limits how many calls you get but gives no number.
We ran Agent Toolbox in [our email verification API benchmark](https://datacircle.dev/best-email-verification-api.txt). We didn't score any Agent Toolbox plan.
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 and 65 others tie for the lowest price per 1,000 emails of the 4,337 plans. [See the best free email verification API plan.](https://datacircle.dev/best-email-verification-api.txt)
[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/agent-toolbox/free
- [Email validation API: best verification providers compared](https://datacircle.dev/best-email-verification-api.txt)
- Get it: https://agent-toolbox.zafermemon87.workers.dev?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Request: `GET https://agent-toolbox.zafermemon87.workers.dev/free/email-verify`
- API key: not needed
- Its API docs: https://agent-toolbox.zafermemon87.workers.dev/llms.txt?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- Sold by: Agent Toolbox (https://agent-toolbox.zafermemon87.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: $0.00
- Per: call
- Billing: free

## Aggregators

- Aggregators: none

## Charges

- Also pays for: nothing else

## Not found

- $ per 1,000: $0.00

## In their words

- Their pitch: Check an email address: format, whether the domain exists and accepts mail (MX records), disposable providers, role accounts and free providers, with a valid / risky / invalid verdict. The mailbox itself is not probed.

## Data

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

## Plan

- Pay: $0

## Rate limit

- Batch: 1

## Speed

- Answer: in the call

## The call

- You send: email
- Method: GET
- Path: /free/email-verify

## About the plan

- Plan: Free
- Who can get it: anyone, with no sign-up or API key, limited per IP address

## The 11 fields the plan's answer can hold

email, verdict, format ok, domain, mail servers, disposable, role account, free provider, reasons, mailbox checked, plain-text summary

## Agent Toolbox's plans (5)

- [Agent Toolbox, free](https://datacircle.dev/validate-email-apis/agent-toolbox/free/llms.txt): $0.00 per 1,000, 50% complete
- [Agent Toolbox, pay as you go](https://datacircle.dev/validate-email-apis/agent-toolbox/pay-as-you-go/llms.txt): $2.00 per 1,000, 50% complete
- [Agent Toolbox, $1 pack](https://datacircle.dev/validate-email-apis/agent-toolbox/1-pack/llms.txt): $2.00 per 1,000, 50% complete
- [Agent Toolbox, $5 pack](https://datacircle.dev/validate-email-apis/agent-toolbox/5-pack/llms.txt): $1.818 per 1,000, 50% complete
- [Agent Toolbox, $20 pack](https://datacircle.dev/validate-email-apis/agent-toolbox/20-pack/llms.txt): $1.667 per 1,000, 50% complete

## Agent Toolbox's calls for this API (2)

- `GET /free/email-verify`: [Agent Toolbox, free](https://datacircle.dev/validate-email-apis/agent-toolbox/free/llms.txt)
- `GET /v1/email-verify`: [Agent Toolbox, pay as you go](https://datacircle.dev/validate-email-apis/agent-toolbox/pay-as-you-go/llms.txt)

## Agent Toolbox's APIs (5)

- [Agent Toolbox: domain WHOIS API pricing, 5 plans](https://datacircle.dev/domain-whois-apis/agent-toolbox/free/llms.txt)
- [Agent Toolbox: email verification API pricing, 5 plans](https://datacircle.dev/validate-email-apis/agent-toolbox/free/llms.txt)
- [Agent Toolbox: web scraping API pricing, 5 plans, POST /free/extract](https://datacircle.dev/web-scraping-apis/agent-toolbox/free-post-free-extract/llms.txt)
- [Agent Toolbox: web scraping API pricing, 5 plans, GET /free/markdown](https://datacircle.dev/web-scraping-apis/agent-toolbox/free-get-free-markdown/llms.txt)
- [Agent Toolbox: business verification API pricing, 4 plans](https://datacircle.dev/business-verification-apis/agent-toolbox/pay-as-you-go/llms.txt)
- [Agent Toolbox: company enrichment API pricing, 4 plans, GET /v1/company/lei](https://datacircle.dev/company-enrichment-apis/agent-toolbox/pay-as-you-go-x402-pay-per-call-get-v1-company-lei/llms.txt)
- [Agent Toolbox: company enrichment API pricing, 4 plans, GET /v1/company/us](https://datacircle.dev/company-enrichment-apis/agent-toolbox/pay-as-you-go-x402-pay-per-call-get-v1-company-us/llms.txt)

## Agent Toolbox: email verification API alternatives

- [pingutil, free API key, POST /v1/verify](https://datacircle.dev/validate-email-apis/pingutil/free-api-key-post-v1-verify/llms.txt): $0.00 per 1,000, 50% complete, 30 days
- [Validemail.co, free, POST /api/v1/bulk](https://datacircle.dev/validate-email-apis/validemail-co/free-post-api-v1-bulk/llms.txt): $0.00 per 1,000, 67% complete, live
- [MailTester Ninja, free, No token](https://datacircle.dev/validate-email-apis/mailtester-ninja/free-no-token/llms.txt): $0.00 per 1,000, 50% complete, live
- [Giggal, free trial, POST /v1/verify-batch](https://datacircle.dev/validate-email-apis/giggal/free-trial-post-v1-verify-batch/llms.txt): $0.00 per 1,000, 67% complete, live
- [2s.io, free](https://datacircle.dev/validate-email-apis/2s-io/free/llms.txt): $0.00 per 1,000, 50% complete

## 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://agent-toolbox.zafermemon87.workers.dev?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://agent-toolbox.zafermemon87.workers.dev/.well-known/x402?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://agent-toolbox.zafermemon87.workers.dev/llms.txt?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://agent-toolbox.zafermemon87.workers.dev/openapi.json?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing
- https://api.cdp.coinbase.com/platform/v2/x402/discovery/resources?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=email-verification-api-pricing