Email Tools
DKIM Checker
Check whether a domain has a DKIM record configured under common selectors.
Enter a domain to check for a DKIM record under common selectors.
Leave the selector blank to check a list of common selectors automatically, or enter a known selector for a precise check.
JustChecker tracks your email authentication records continuously.
Frequently Asked Questions
DKIM cryptographically signs outgoing email so the receiving server can verify the message content wasn't altered in transit and genuinely originated from a server holding your domain's private key - a stronger, tamper-evident guarantee than SPF's sender-IP-based check.
DKIM records are published at a selector-specific subdomain (e.g. selector1._domainkey.yourdomain.com) chosen by whichever email service configured it - there's no single, universal location, so checking known common selector names is the practical way to discover it.
Your email service's own DKIM setup documentation will specify its exact selector name - you can look up that specific selector's DNS record directly if it isn't among the commonly-checked ones.
Yes, and this is common when using multiple sending services (e.g. your primary email provider plus a separate marketing platform) - each service typically uses its own distinct selector, and multiple can coexist without conflict.
No - it's one authentication signal among several; sender reputation, content, and DMARC alignment all still factor into spam filtering decisions independently of a valid DKIM signature.
Both use public/private key cryptography, but DKIM signs individual email messages for authenticity verification, while an SSL certificate secures a website's HTTPS connection - entirely separate systems serving different purposes.