Free DKIM Record Checker & Selector Validator
Inspect and test your DomainKeys Identified Mail (DKIM) selector records. Verify 2048-bit cryptographic public keys and prevent cold email spoofing.
Why Cold Outbound Teams Use Our Free DKIM Checker
Custom selector test (e.g. google, default, k1)
Public key bit-length analyzer (1024-bit vs 2048-bit)
DKIM syntax verification
Email Deliverability Standards (US & UK Outbound Guidelines)
In February 2024, Google Workspace and Yahoo introduced strict anti-spam enforcement rules that mandate proper SPF, DKIM, and DMARC authentication for all outbound mailboxes. If your DNS records have syntax errors or exceed the 10-lookup threshold, incoming mail servers will silently route your cold outreach into the Spam folder or reject connections entirely.
Requires valid physical postal address in signatures, accurate From header identification, and clear opt-out mechanics.
Permits B2B outreach under legitimate interest when targeted to relevant corporate decision-makers with authenticated sender identity.
Frequently Asked Questions About DKIM Checker
What is a DKIM selector?
A DKIM selector is a string tag that points to the specific public key used to sign your outgoing emails. For example, Google Workspace uses "google._domainkey.yourdomain.com".
Should I use 1024-bit or 2048-bit DKIM keys?
Always use 2048-bit DKIM keys whenever supported. 1024-bit keys are considered legacy and may receive lower deliverability scores from modern spam filters.
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