Email Verification API

Built by Developers, for Developers.

Before you call your sending API, call Listclean. Our real-time verification API tells you if an email is valid, invalid, or risky - so you know whether to send, block, or review.

REAL-TIME VERIFICATION

Single Email Verification API

Call our real-time Email Verification API wherever an email enters your application. From signups and checkout flows to lead forms, newsletters, CRM entries, and user invitations, validate every address directly within your existing workflow.

curl \ --request GET \ --url 'https://api.listclean.xyz/v1/verify/email/[email protected]' \ --header 'X-Auth-Token: YOUR_API_TOKEN' \ --header 'Accept: application/json'
curl \ --request POST \ --url 'https://api.listclean.xyz/v1/verify/email/batch' \ --header 'X-Auth-Token: YOUR_API_TOKEN' \ --header 'Accept: application/json' \ --header 'Content-Type: application/json' \ --data '{ "emails": [ "[email protected]", "[email protected]", "[email protected]" ] }'

ASYNC BATCH VERIFICATION

Bulk Email Verification API

Call our Bulk Email Verification API to verify large volumes of email addresses asynchronously. Submit your batch and receive a unique List ID while Listclean processes it in the queue. Use the List ID to track status and retrieve the verified results once processing is complete.

Why Verification Matters

The cost of unverified emails

Sending to unverified email addresses doesn't just waste money it actively damages your sender reputation and deliverability rates.

Reputation Damage

High bounce rates signal poor list quality to mailbox providers, triggering spam filters and permanently damaging your domain reputation.

How We Prevent It:
  • SMTP verification pings actual servers
  • 98.5% accuracy before you send
  • Real-time mailbox validation

Blacklist Risk

Spam traps and honeypots can blacklist your domain instantly, making it nearly impossible to reach real inboxes across all campaigns.

How We Prevent It:
  • Updated trap databases maintained daily
  • Behavioral pattern analysis
  • Suspicious address identification

Resource Waste

Catch-all domains and role-based addresses lead to low engagement rates, wasted sending costs, and diluted campaign metrics.

How We Prevent It:
  • Intelligent quality scoring flags risks
  • Catch-all domain identification
  • Disposable email detection

By The Numbers

Built for speed and scale

500K

Verifications per hour

98.5%

Accuracy

<2s

Average response time

24/7

API availability

VERIFIED REVIEWS

What teams say

after their first email verification api run.

Real feedback from teams that cleaned their lists, improved inbox placement, and gained better visibility into list quality.

Efficient, reliable, and user-friendly

“We have been using Listclean as part of our email marketing and lead validation process, and the results have been outstanding. The platform is incredibly easy to use, fast, and delivers highly accurate email verification results.”

AG
Amol GunjalMarketing Campaign Manager · Pomeroy · ENTERPRISE Hebron, Kentucky

Works well, easy to use, and fairly priced

“Very nice tool, easy to use and fairly priced. It helps avoid the worst spam traps.”

RS
Ronnie SobergHead of Business Development · E-communication LTD · SMB Metro Manila

Best out there for real

“Listclean is an absolute lifesaver for email marketers. Its debouncing tool effortlessly cleans my lists by catching bounces, invalid addresses, and spam traps in seconds, boosting deliverability without any hassle. Highly recommended.”

ZB
Zenzi BernardDeputy CEO · 360 Crypto Mining · SMB New York City Metropolitan

Email verification with a great interface

“This software has been easy to use and navigate. It is efficient and effective. The program goes above and beyond to reduce bounce rates. The email validation is accurate, the platform is user-friendly, and it is extremely cost-effective.”

HD
Holly DHR Director · Hospital & Health Care · ENTERPRISE United States

A cost-effective game-changer for email list verification

“Listclean has transformed how I manage email campaigns by delivering exceptional accuracy at an affordable price. The platform is incredibly user-friendly. Uploading CSV files and receiving verified results takes just minutes.”

PB
Pawan BishtSr. Developer - Team Lead · StarClinch · SMB India

Best verification tool on the market

“Overall, I enjoyed using Listclean. Their tool has allowed me to avoid damaging my domains and maintain high deliverability. It is very affordable too. I would recommend it to anyone. I liked how fast and simple the platform is.”

BM
Brian M.Founder · Marketing and Advertising · SMB United States

Great tool for quick list cleaning

“Listclean helps me remove invalid, spammy, or risky email addresses from my lists. This improves deliverability, reduces bounce rates, protects my sender reputation, and saves time and money on email campaigns.”

CS
Cosmin M. SevastreFounder · Self · STARTUP Romania

My experience with Listclean has been great

“My experience with Listclean has been amazingly positive. I use it regularly as part of my cold email campaigns, and it helps improve deliverability and protect our domain. Highly recommended.”

SG
Sagar GoyalCMO · Email Marketing · SMB India

Listclean helped me cut bounce rates and save time

“My experience with Listclean has been overwhelmingly positive. I use it regularly as part of my cold email workflow, and it has become a key tool for improving deliverability and protecting our domain reputation.”

FN
Francisco NavarroTechnical Product Owner · Fashion & Apparel and Retail · SMB Spain

The best bulk email verification tool

“I run a cold email agency and send thousands of emails to different addresses every day. Listclean helps me keep my lists cleaner and my campaigns safer.”

JK
Joshua KontohCEO · ProficientProspecting · SMB United States

An awesome email verifier

“We have a huge customer email list and need to promote our new products by email. We need to verify the list before sending, and Listclean helps us do that effectively.”

JB
Jennie BairdMarketing Engineer · Unipro · ENTERPRISE London, England

The best verification service

“I do email marketing campaigns for numerous companies. I have used various list verification services for years. Not only is Listclean the most accurate, but their prices are extremely good. Look no further.”

KS
Kenneth SimonOwner · Marketing & Advertising · SMB United States

Listclean is excellent for email cleaning

“An excellent experience with Listclean. Their customer support is excellent, turnaround time is quick, and the email list cleaning is flawless. A truly professional company I would recommend without hesitation.”

JH
Jason H.CEO · Apparel & Fashion · SMB United States

Amazing verification tool for cold emailers

“An absolutely amazing cold email verification tool to help ensure your leads are not bouncing.”

AA
AyaanSelf-Employed · STARTUP India

Great, detailed, and fast service

“Before using Listclean, I had approximately a 20% bounce rate, which had a huge impact on my domain. After I started using Listclean, this rate dropped to almost 0%. I am extremely satisfied.”

PG
Peter GillSelf-Employed · Logistics and Supply Chain · SMB United States

Security & Compliance

Your data is safe with us

We never share your data with third parties. All verification happens on our secure infrastructure with enterprise-grade encryption.

SOC 2
Type II
GDPR
Compliant
ISO 27001
Certified
256-bit
Encryption

Frequently asked

Questions about our API,

integration and how it works.

Everything developers need to know about real-time verification, batch processing, rate limits, credits, and getting started with the Listclean API.

Top 10 Questions
Answer 01 of 10

What is the Listclean Email Verification API?

The Listclean Email Verification API lets developers verify email addresses directly inside their applications.

  • Verify a single email address in real time.
  • Submit thousands of email addresses using the Batch Verification API.
  • Integrate verification into signups, checkout flows, lead forms, CRMs and other applications.
  • Receive structured API responses that your application can process automatically.
Use the same Listclean verification engine directly from your application.

Ready to make your first Email Verification API call?

Get 25 free verification credits and start testing the Listclean Email Verification API. No credit card required.