Syntax & Format Validation
RFC-compliant format checking catches malformed addresses, typos, and invalid characters before deeper checks begin.
Verify Any Address
Verify Email Addresses Before You Send
Use one email verifier for a single address, a permission-based CSV or XLSX list, or an application workflow. Mailthentic reports valid, risky, invalid, and unknown evidence without promising future delivery.
Free DNS check, no signup required. Verify a list or use the verification API for product workflows.
Multi-Layered Checks
How Our Email Verification Works
Each address is evaluated with layered checks, and uncertain mail server responses remain visible in the result.
Domain & DNS Verification
Confirms the domain resolves and has an inbound mail route, filtering out addresses whose domains cannot receive mail.
MX Record Lookup
Queries mail exchange records to verify the domain has active mail servers configured and ready to accept messages.
Disposable Email Detection
Identifies known temporary and disposable email services so teams can apply their own list policy.
Role-Based Address Filtering
Flags generic role addresses (info@, admin@, support@) that typically have lower engagement and higher complaint rates.
SMTP Mailbox Confirmation
When enabled, connects to the recipient mail server for available recipient evidence without sending an email message.
Transparent Evidence
Layered Email Verification Signals
Mailthentic combines enabled and available checks, preserves uncertainty, and explains why an address reached its status.
1
Syntax Validation
RFC 5322 format check catches typos, missing @, spaces, and invalid characters.
2
Domain DNS Check
Confirms the domain exists and resolves. Detects NXDOMAIN (non-existent domains).
3
MX Record Lookup
Verifies mail exchange records exist and identifies the email provider.
4
SPF Verification
Checks for Sender Policy Framework records that authorize mail servers.
5
DKIM Check
Detects DomainKeys Identified Mail records with auto-selector detection.
6
DMARC Validation
Verifies DMARC policy and reporting configuration for authentication compliance.
7
SMTP Mailbox Verification
Connects to the mail server for available recipient evidence and preserves ambiguity when acceptance cannot prove a mailbox.
8
Disposable Detection
Checks against Mailthentic's maintained disposable-domain data.
9
Catch-All Detection
Probes with random addresses to detect domains that accept all mail regardless of mailbox existence.
Provider Intelligence
How We Handle Different Email Providers
Not all email providers respond the same way. Our engine adapts verification strategy per provider.
| Provider | SMTP Response | Our Approach |
|---|---|---|
| Gmail / Google Workspace | 250 for all addresses | Classified as "ambiguous", DNS checks applied, mailbox unconfirmed |
| Microsoft 365 / Outlook | 250 for all addresses | Same ambiguous treatment with domain health factored in |
| Yahoo / AOL | 550 for invalid, aggressive rate limiting | Throttled probing with automatic retry and backoff |
| ProtonMail | 250 for all addresses | DNS-only mode, mailbox unconfirmable |
| Self-hosted (Postfix, Exim) | 550 for invalid users | Full SMTP verification with greylisting retry (up to 3 attempts) |
Learn more: SMTP Response Codes Explained
Syntax
Format Validation
DNS + MX
Domain Routing
Risk
Disposable and Role Signals
SMTP
Available Recipient Evidence
Verification Modes
DNS-Only vs Full SMTP Verification
Choose the right verification depth for your needs.
| Feature | DNS-Only | Full SMTP |
|---|---|---|
| Syntax check | ✓ | ✓ |
| Domain / DNS check | ✓ | ✓ |
| MX record lookup | ✓ | ✓ |
| SPF / DKIM / DMARC | ✓ | ✓ |
| Disposable detection | ✓ | ✓ |
| SMTP mailbox confirmation | ✗ | ✓ |
| Catch-all detection | ✗ | ✓ |
| Greylisting retry | ✗ | ✓ |
| Recipient evidence | Not checked | When the server permits it |
| Availability | Free tool | Free account |
Clear Outcomes
Email Verification Results You Can Trust
Every verified address is categorized into one of four clear outcome statuses.
Valid
Address exists, domain is active, and the mailbox can receive messages.
Risky
Address may be valid but carries risk, such as a catch-all domain or role-based local part.
Invalid
Address does not exist, domain has no mail server, or syntax is malformed.
Unknown
Server did not respond conclusively. The address may or may not be valid.
Use Cases
Email Verification Use Cases
Pre-Campaign List Cleaning
Verify your entire email list before every send with the bulk email verifier. Remove invalid and risky addresses to reduce hard bounces, protect sender reputation, and maximize inbox placement rates.
CRM Data Hygiene
Keep your CRM clean with regular verification. Identify stale addresses, detect disposable signups, and maintain trustworthy data for automation workflows and reporting.
Registration Form Validation
Validate email addresses at the point of capture. Block disposable and invalid addresses before they enter your database.
Lead Qualification
Score and filter inbound leads by email quality. Prioritize verified business emails and flag risky or role-based addresses that indicate low conversion potential.
256-bit SSL Encrypted
No Emails Sent During Verification
No Data Reselling, Ever
Multi-Signal Verification
Frequently Asked Questions
What does email verification check?
Mailthentic checks syntax, domain existence, MX availability, disposable-domain data, role-based patterns, and optional SMTP recipient evidence without sending an email.
How fast is the verification process?
Verification time depends on DNS and receiving mail server behavior. Use asynchronous status checks and a client timeout. Choose bulk verification when a file can be processed as a job.
Does verification send emails to the addresses being checked?
No message body is transmitted during verification. DNS and MX checks are passive lookups. SMTP verification closes the session before the message-data stage.
What is the difference between DNS-only and SMTP verification?
DNS-only validation checks domain existence, MX records, and SPF or DMARC configuration. SMTP verification can add recipient evidence, but acceptance does not always prove that the specific mailbox exists.
How accurate is email verification?
No email verification result guarantees future delivery. Mailthentic combines syntax, DNS, MX, risk, and available SMTP evidence. Unknown or ambiguous outcomes remain visible when a provider does not expose enough information.
What is catch-all detection?
Catch-all domains accept email for any address, even non-existent ones. Mailthentic detects these by probing with random addresses, if both accept, the domain is catch-all. Results are classified as "risky" because individual mailbox existence cannot be confirmed.
How much does email verification cost?
Eligible new accounts can receive 250 verification credits without a credit card. Current packs, account limits, and credit expiry are shown on the pricing page and in the account.
Can I verify emails in bulk?
Yes. Upload CSV or XLSX to the bulk verifier. Mailthentic processes unique addresses within current account limits, reports asynchronous progress, and exports CSV or XLSX results by status.
Can I integrate verification into my app?
Yes. Our REST API lets you verify emails in real time from any application. Simple JSON endpoints, API key authentication, and webhook support. Integrate in minutes.
Explore More
Related Email Verification Tools
Bulk Email Verifier
Upload CSV files and clean entire contact lists with parallel processing and real-time tracking.
DNS Email Validation
Validate MX records, SPF, and DMARC configuration without SMTP connections for fast domain-level checks.
Domain Health Check
Audit your domain's email authentication setup including SPF, DKIM, and DMARC policy configuration.
Provider-Specific Verification Guides
Start Verifying Email Addresses Today
Create an account, review the current credit allowance, and choose single, bulk, or API verification. No credit card is required to create the account.