What is DKIM and why is it important for email?

DKIM (DomainKeys Identified Mail) is an email authentication protocol that uses digital signatures to verify that emails genuinely come from your domain. It's important because it prevents email spoofing, improves deliverability rates, and helps protect your domain reputation. Without DKIM, your emails are more likely to be flagged as spam or rejected by receiving mail servers.

How do I find my DKIM selector?

Your DKIM selector depends on your email service provider. Common selectors include 'default', 'google' (for Google Workspace), 'amazonses' (for Amazon SES), or custom selectors you've created. Check your email provider's documentation or your mail server configuration to find the correct selector. You can also try common selectors in DKIM Checker to identify which one is active.

What does it mean if my DKIM check fails?

A failed DKIM check typically indicates that the DKIM record is not properly published in your DNS, the selector is incorrect, or the record is misconfigured. Verify that your DNS provider has the correct TXT record with the proper public key, ensure the selector matches your mail server configuration, and allow time for DNS propagation (up to 48 hours) after making changes.

Can I have multiple DKIM records for one domain?

Yes, you can have multiple DKIM records for the same domain by using different selectors. This allows you to rotate keys for security purposes, use different keys for different mail servers, or transition to new keys without disrupting email delivery. Each selector points to a separate TXT record containing its own public key.

How often should I check my DKIM records?

You should check your DKIM records whenever you make changes to your email configuration, switch email providers, or notice delivery issues. Additionally, perform regular security audits (monthly or quarterly) to ensure DKIM remains properly configured. This helps maintain consistent email deliverability and prevents authentication failures.

DKIM Checker - Verify Your Email Authentication

The DKIM Checker is a powerful tool that verifies whether your domain's DKIM (DomainKeys Identified Mail) records are correctly configured and published in DNS. DKIM authentication is essential for email deliverability and security, helping prevent spoofing and improving your sender reputation. Use this tool to validate your email authentication setup in seconds.

How to Use DKIM Checker

DKIM Checker is a straightforward tool designed to verify your domain's DKIM records and ensure proper email authentication. Follow these simple steps to check your DKIM configuration:

Enter Your Domain: Input your domain name in the search field (e.g., example.vn)
Select Selector: Choose the DKIM selector associated with your email service provider or mail server
Click Check: The tool will query your DNS records and retrieve DKIM information
Review Results: Examine the DKIM public key and authentication status displayed
Verify Configuration: Confirm that the DKIM record is properly published and correctly formatted
Troubleshoot Issues: If verification fails, check your DNS settings and selector configuration

When to Use DKIM Checker

DKIM Checker is essential for maintaining email deliverability and security. Use this tool in the following scenarios:

Email Setup Verification: After configuring DKIM for your domain, verify that records are correctly published in DNS
Troubleshooting Delivery Issues: When emails are being marked as spam or rejected, check if DKIM authentication is properly configured
Domain Migration: During domain transfers or email service provider changes, ensure DKIM records are correctly updated
Security Audits: Regularly check DKIM status as part of your email security and compliance review
SPF/DMARC Setup: Verify DKIM alongside SPF and DMARC records for comprehensive email authentication
Third-party Service Integration: When integrating marketing automation or transactional email services, confirm DKIM validation

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Technical Information About DKIM

DKIM (DomainKeys Identified Mail) is an email authentication protocol that uses cryptographic signatures to verify email authenticity and prevent spoofing. Understanding DKIM helps optimize your email security infrastructure.

How DKIM Works

Digital Signature: Your mail server signs outgoing emails with a private key stored on your server
DNS Publication: The corresponding public key is published in your DNS records as a TXT record
Recipient Verification: Receiving mail servers retrieve the public key from DNS and verify the email signature
Authentication Result: If the signature is valid, the email passes DKIM authentication and improves deliverability

DKIM Record Format

Selector: A unique identifier that allows multiple DKIM keys per domain (e.g., 'default', 'google', 'mail')
Public Key: The RSA public key encoded in base64 format within the TXT record
Key Version: Version identifier for key rotation and management purposes
Service Type: Specifies which services the key is valid for (typically email)

Frequently Asked Questions

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