Triple Verification

99.9% deliverability. Guaranteed.

Our Triple Verification system checks every email through three layers: Syntax Check → MX/DNS Validation → SMTP Handshake. Catch bounces before they happen.

The Process

Verification

Every email passes through three rigorous validation steps before we mark it deliverable.

01

Syntax Check

Validates email format, checks for typos, and normalizes the address according to RFC 5322 standards.

  • RFC 5322 compliance
  • Domain format validation
  • Local part verification
  • Common typo detection
02

MX/DNS Validation

Queries DNS records to verify the domain exists and has valid mail exchange (MX) servers configured.

  • MX record lookup
  • DNS resolution check
  • Mail server discovery
  • Domain age verification
03

SMTP Handshake

Performs a real-time ping to the mail server without sending an email to verify the mailbox exists.

  • Real-time server ping
  • Mailbox existence check
  • Catch-all detection
  • Greylisting handling
Smart Detection

Verification

We don't just check if an email is valid. We identify risky addresses that could hurt your sender reputation.

Disposable Email Detection

Identifies temporary/burner emails from 50,000+ known disposable domains (Mailinator, Guerrilla Mail, etc.).

Role-Based Detection

Flags generic addresses like info@, support@, sales@ that often bounce or go unread.

Catch-All Detection

Identifies domains configured to accept all emails, reducing false positives in your lists.

Accept-All Detection

Detects servers that claim to accept everything, helping you filter low-confidence addresses.

Live Example

See It

Real verification results in under 200ms.

Verification Results

john@company.com

Valid

147ms

test@mailinator.com

Disposable

Invalid

89ms

info@startup.io

Role-based

Risky

203ms

sarah@techcorp.io

Valid

156ms

bounce@invalid.xyz

No MX records

Invalid

312ms

Average response time181ms
verification_response.json
1{
2 [#e06c75]">"email": [#98c379]">"john.smith@company.com",
3 [#e06c75]">"valid": [#d19a66]">true,
4 [#e06c75]">"deliverable": [#d19a66]">true,
5 [#e06c75]">"result": {
6 [#e06c75]">"syntax_valid": [#d19a66]">true,
7 [#e06c75]">"mx_found": [#d19a66]">true,
8 [#e06c75]">"mx_host": [#98c379]">"mail.company.com",
9 [#e06c75]">"smtp_check": [#d19a66]">true,
10 [#e06c75]">"mailbox_exists": [#d19a66]">true,
11 [#e06c75]">"catch_all": [#d19a66]">false,
12 [#e06c75]">"disposable": [#d19a66]">false,
13 [#e06c75]">"role_based": [#d19a66]">false,
14 [#e06c75]">"free_provider": [#d19a66]">false
15 },
16 [#e06c75]">"risk_level": [#98c379]">"low",
17 [#e06c75]">"confidence_score": [#d19a66]">98,
18 [#e06c75]">"verification_time_ms": [#d19a66]">147
19}

99.9%

Accuracy

<200ms

Avg. Response

50K+

Disposable Domains

10M+

Emails Verified Daily

Results

Protect Your

See how teams are reducing bounce rates with Cleanlist verification.

Ma

MarketingPro

Email Marketing

Bounce Rate

0.8%

-94%
Sa

SalesForce Co

SaaS

Deliverability

99.2%

+12%
Le

Lead Gen Inc

Lead Generation

Valid Emails

847K

/month
Ou

Outreach Labs

Sales Engagement

Sender Score

98

+23

Frequently Asked Questions

How does Cleanlist's email verification work?

+

Cleanlist uses triple-layer verification: syntax validation (RFC 5322 compliance), DNS/MX record lookup (domain exists and accepts email), and SMTP handshake verification (mailbox exists). We also detect catch-all domains, disposable emails, role-based addresses, and spam traps.

What accuracy rate does email verification achieve?

+

Cleanlist achieves 99.9% deliverability on verified emails. Our triple verification process catches invalid, risky, and undeliverable addresses before you send, reducing bounce rates to under 1%.

How does catch-all email detection work?

+

Catch-all domains accept all emails regardless of whether the specific mailbox exists. Cleanlist detects catch-all servers and flags these addresses as 'risky' so you can handle them separately - either exclude them from campaigns or test with lower volume.

Can I verify emails in bulk?

+

Yes. Upload CSV files with up to 10,000+ emails per batch. Cleanlist verifies each email through all three layers and returns results with status (valid, invalid, risky), confidence score, and reason codes. Bulk verification typically completes within minutes.

How much does email verification cost?

+

Email verification uses the same credit system as enrichment: 1 credit = 1 email verified. The free plan includes 30 credits per month. Paid plans start at $29/month for 500 credits. No setup fees or minimum commitments.

Your next deal is hiding in dirty data.

30 free credits. 90 seconds to set up. No credit card.