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DKIM Record Check - Validate Your Email Signature

Check your domain's DKIM (DomainKeys Identified Mail) record to ensure proper email authentication and improve deliverability. Get instant validation with detailed recommendations.

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What is a DKIM Record Checker?

A DKIM record checker validates your domain's DomainKeys Identified Mail configuration by querying DNS records with the specified selector and verifying the cryptographic signature setup for email authentication.

Selector Support

Check DKIM records for any selector including default, google, selector1, or custom selectors configured by your email provider.

Syntax Validation

Verify DKIM record syntax including public key format and required parameters to ensure proper authentication.

Enhanced Security

DKIM signatures prevent email tampering and verify sender authenticity, improving your email reputation.

How DKIM Authentication Works

Cryptographic signatures for email integrity

1

Email Signing

When sending an email, your mail server adds a DKIM signature to the email header using a private key. This signature covers specific parts of the email content.

2

DNS Lookup

The receiving server extracts the selector and domain from the DKIM signature, then queries DNS for the public key at selector._domainkey.domain.com.

3

Verification

The receiving server uses the public key to verify the signature. If valid, the email is authenticated and more likely to reach the inbox.

Why DKIM Records Matter

Essential for email authentication and deliverability

Prevent Email Tampering

DKIM signatures ensure email content hasn't been modified during transit. Any changes to signed headers or body content will cause verification to fail, protecting against man-in-the-middle attacks.

Boost Deliverability

Email providers like Gmail and Outlook strongly favor emails with valid DKIM signatures. Proper DKIM configuration significantly improves inbox placement rates and sender reputation.

Verify Authenticity

DKIM proves that emails were actually sent from your authorized servers, not from attackers attempting to impersonate your domain. This builds trust with both email providers and recipients.

DMARC Foundation

DKIM is a critical component of DMARC (Domain-based Message Authentication, Reporting, and Conformance), which provides comprehensive email authentication and reporting.

Common DKIM Selectors by Provider

Find your DKIM selector based on your email service

Google Workspace

Google uses the selector google for DKIM signing.

DNS record: google._domainkey.yourdomain.com

Microsoft 365

Microsoft typically uses selector1 or selector2.

DNS record: selector1._domainkey.yourdomain.com

Generic / Default

Many email providers use default or k1 as selectors.

DNS record: default._domainkey.yourdomain.com

Find Your Selector

Check your email provider's documentation or inspect email headers to find the s= value in DKIM-Signature.

Related Resources

Learn more about DKIM and email authentication

Mastering Email Authentication Guide

Complete guide to implementing SPF, DKIM, and DMARC for optimal email security.

How to Avoid Landing in Spam - Full Guide

Comprehensive guide to preventing your emails from being marked as spam.

Setup DKIM, SPF, DMARC & BIMI

Step-by-step guide to configuring all email authentication protocols including BIMI.

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Frequently Asked Questions About DKIM Records

Everything you need to know about DKIM authentication

DKIM (DomainKeys Identified Mail) is an email authentication method that uses cryptographic signatures to verify that an email was sent by an authorized server and hasn't been tampered with during transit. It adds a digital signature to email headers that receiving servers can validate.

Use our free DKIM checker tool to instantly check your domain's DKIM record. Enter your domain name and DKIM selector, and our tool will query your DNS records to find and validate your DKIM configuration. Common selectors include "default", "google", "selector1", or "k1".

A DKIM selector is a unique identifier that allows a domain to have multiple DKIM keys. It's part of the DNS record name format: selector._domainkey.yourdomain.com. Common selectors include "default", "google" (for Google Workspace), "selector1" or "selector2" (for Microsoft 365), or custom selectors set by your email provider.

Common reasons for DKIM record failures include: no DKIM record published in DNS, using the wrong selector, invalid syntax (missing "p=" parameter), incorrect public key format, or DNS propagation delays after setup. Our DKIM checker will identify specific issues.

Your DKIM selector depends on your email service provider. Check your email platform's documentation: Google Workspace uses "google", Microsoft 365 uses "selector1" or "selector2", and many providers use "default" or "k1". You can also check your email headers to see the "d=" and "s=" values in the DKIM-Signature.

Yes! Unlike SPF records, you can have multiple DKIM records for a single domain by using different selectors. This is useful when using multiple email service providers or when rotating keys for security purposes.

Yes! Our DKIM checker is completely free to use. You can check your domain's DKIM records as many times as needed to ensure your email authentication is properly configured.

Without DKIM authentication, your emails are more likely to be marked as spam or rejected by receiving mail servers. DKIM is a critical component of email authentication alongside SPF and DMARC. Consider using email warmup services to improve your sender reputation.

Improve Your Email Deliverability

Need help with email authentication and deliverability? Mailwarm helps you build sender reputation and ensure your emails reach the inbox.

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