DKIM record validator
Enter your domain and DKIM selector to validate the key — check algorithm, key length, and mandatory tags in seconds.
Frequently asked
What's a DKIM selector?
A DKIM selector is a name that identifies which key to use. Your email provider assigns it — common examples: 'default', 'google', 'selector1', 'key1'. Check your provider's documentation. The tool prepends it to '_domainkey.yourdomain' automatically.
What key size is acceptable for DKIM?
1024-bit RSA is the absolute minimum and is still widely supported. 2048-bit RSA is the current best practice — provides strong security without impacting deliverability. Ed25519 (256-bit) is16 the modern alternative: smaller keys, faster signing. Keys under 1024 bits are flagged as failures and may cause rejections.
Why use DKIM when I already have SPF?
SPF verifies the sending server; DKIM verifies the message content hasn't been tampered with. SPF can break when mail is forwarded; DKIM survives forwarding. Both together with DMARC provide comprehensive email authentication.
How do I find my DKIM selector?
Check your email provider's setup instructions. Gmail/Google Workspace uses 'google'. Microsoft 365 uses 'selector1' and 'selector2'. Mailchimp, SendGrid and other ESPs document it in their DNS setup guides. Most providers give you 2-3 selectors for key rotation.
Publish your DKIM key on DNScale
Built and operated in the EU. The same anycast network that powers this tool serves every DNScale-hosted zone.
Publish your DKIM key on DNScale