📧 Domain Validation
🔒 Only queries public DNS records. No emails sent, no data stored.
Free online tool to check domain email authentication records. Parse SPF, DKIM, DMARC records with optimization suggestions. Pure frontend.
🔒 Pure Frontend · No Server UploadsThe SPF/DKIM/DMARC Validator is an online tool designed for mail administrators and domain owners. It quickly checks domain SPF, DKIM, and DMARC email authentication record configurations to help ensure email deliverability and prevent email spoofing or spam marking.
With major email providers like Gmail and Yahoo strengthening email authentication requirements, properly configuring SPF, DKIM, and DMARC has become essential for sending email. This tool helps you quickly diagnose configuration issues and provides optimization suggestions.
SPF Record Parsing: Query and parse domain SPF TXT records, check authorized sending servers, include mechanisms, and DNS lookup count limits.
DKIM Record Check: Check domain DKIM TXT records and verify public key configuration.
DMARC Policy Validation: Query and parse domain DMARC TXT records, check policy configuration (none/quarantine/reject) and reporting settings.
Configuration Scoring: Provide a comprehensive score and optimization suggestions based on the three authentication records.
1. Enter the domain you want to check (e.g., example.com) in the input field.
2. Click the "Validate" button to automatically query DNS records.
3. Review the SPF, DKIM, and DMARC check results.
4. Follow the suggestions to optimize your configuration and ensure complete email authentication.
Mail Configuration Check: Verify SPF/DKIM/DMARC are correctly set up after configuring a new mail service.
Deliverability Optimization: Check authentication configuration when emails bounce or land in spam.
Domain Security Audit: Regularly check email authentication to prevent domain abuse for spoofing.
Migration Verification: Verify authentication records need updating after changing email providers.
SPF (Sender Policy Framework) uses DNS TXT records to specify authorized sending IP addresses and servers. DKIM (DomainKeys Identified Mail) uses asymmetric cryptography to sign emails, with receiving servers verifying signatures using the public key in DNS. DMARC (Domain-based Message Authentication, Reporting and Conformance) builds on SPF and DKIM, letting domain owners specify failure handling policies. Together, they form a complete email authentication system that is the foundation of modern email security.
This is an online tool that checks domain SPF, DKIM, and DMARC email authentication record configurations. Enter a domain and the tool will query DNS records and verify the configuration.
SPF (Sender Policy Framework) is a DNS record that specifies which mail servers are authorized to send email on behalf of the domain.
DKIM (DomainKeys Identified Mail) is an email signing technology. The sending server signs emails with a private key, and receiving servers verify the signature using the public key in DNS.
DMARC builds on SPF and DKIM, letting domain owners specify what to do when emails fail authentication (reject, quarantine, or allow) and receive verification reports.
Proper SPF, DKIM, and DMARC configuration prevents email spoofing, improves deliverability, and avoids spam marking. Gmail and Yahoo now require senders to configure these records.
RFC 7208 limits SPF resolution to 10 DNS lookups. Exceeding this limit causes SPF validation to fail (PermError). Be careful with include and redirect mechanisms.