DKIM Checker: Validate Your DKIM Record and Email Signature
Check your DKIM record, verify selectors and signatures, validate DNS configuration, and detect issues affecting email authentication and deliverability.
Results
- Free DKIM lookup
- Instant results
- No signup required
What does this DKIM checker analyze?
Run a complete DKIM lookup and get a clear diagnosis of your DNS record, selector configuration, and deliverability impact.
DKIM record lookup
Retrieve the DKIM TXT record published in your DNS using the selector.
Selector validation
Ensure your DKIM selector is correctly configured and accessible.
DKIM signature verification
Check whether emails are properly signed and validated by receivers.
Public key analysis
Validate DKIM key format, length, and cryptographic strength.
DKIM errors and warnings
Detect missing records, invalid keys, and alignment issues.
Deliverability impact
How DKIM affects authentication, message integrity, and inbox placement.
DKIM Record Examples
Here are common DKIM setups used across popular email providers.
Google Workspace
selector1._domainkey.example.com
Microsoft 365
selector1-example-com._domainkey.example.onmicrosoft.com
Mailgun
k=rsa; p=PUBLIC_KEY
Basic DKIM record
v=DKIM1; k=rsa; p=PUBLIC_KEY
Multiple selectors
selector1 / selector2 used for rotation
2048-bit key
Recommended secure DKIM configuration
How DKIM Works and Why It Matters
DKIM (DomainKeys Identified Mail) is an authentication method that uses cryptographic signatures to verify that your emails were not altered during transmission.
When an email is sent, it is signed with a private key. The receiving server retrieves the public key from your DNS and verifies the signature. If valid, DKIM passes.
A valid DKIM setup improves authentication, protects message integrity, and supports DMARC alignment. It is a core component of email deliverability.
DKIM records use selectors:
Example:
mailX Related Email Authentication Tools
Check, validate, and generate SPF, DKIM, and DMARC records to improve email deliverability and protect your domain.
Common DKIM Errors This Tool Detects
Missing DKIM record
No DKIM public key found in DNS.
Invalid selector
Selector does not match any DNS entry.
Invalid public key
Incorrect formatting or corrupted key.
Weak key length
1024-bit keys reduce security and trust.
DKIM signature missing
Emails are not signed properly.
Alignment issues
Domain mismatch affecting DMARC validation.
DKIM, Email Authentication & Deliverability Guides
DKIM Failures Complete Guide
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Free DKIM Checker to Validate Your DKIM Record
Use this DKIM checker to perform a DKIM lookup, validate your DomainKeys Identified Mail record, and detect configuration issues affecting email authentication and deliverability.
DKIM uses cryptographic signatures to verify that your emails have not been altered during transmission and are sent from a trusted domain. If your DKIM record is missing, invalid, or misconfigured, your emails are more likely to fail authentication checks or be filtered into spam.
This tool helps you validate selectors, check DNS records, and confirm that your emails are properly signed and trusted by receiving servers.
DKIM Record Check Results
Status & Record
DKIM status (valid / missing / error) & full DKIM record
Analysis Summary
Selector validity, key strength & DNS configuration
Issues & Fixes
Detected problems & recommended fixes
Fix Your Deliverability with an Expert
Get a personalized audit of your DKIM, SPF, and email setup. Identify what’s hurting your deliverability and get clear, actionable fixes in a 30-minute session.