Free DKIM Record Lookup
Auto-discover DKIM records across 50+ common selectors, or look up a specific selector. Identify which email services sign messages for your domain.
Scans common DKIM selectors via DNS-over-HTTPS to discover which email services sign messages for your domain.
What is a DKIM Record?
A DKIM (DomainKeys Identified Mail) record is a DNS entry that enables email senders to sign outgoing messages with a unique cryptographic signature. This signature acts as a digital fingerprint, allowing recipients to verify that an email genuinely originated from the claimed domain and hasn't been altered in transit.
Think of it like receiving a letter sealed with a wax stamp — the stamp indicates the letter is authentic and hasn't been tampered with during its journey. As of 2023, approximately 80% of Fortune 500 companies use DKIM to secure their email communications.
How DKIM Authentication Works
Generate Key Pair
A DKIM generator creates a private key (kept secret on your mail server) and a public key (published in your DNS).
Sign Outgoing Emails
Your mail server uses the private key to create a unique encrypted signature for each outgoing email, added to the header.
Verify on Receipt
The receiving server retrieves your public key from DNS and verifies the signature. If it matches, the email is trusted.
Common DKIM Issues
Misconfigured DNS Records
Typos or incorrect entries in TXT records are the most common cause. Double-check for missing quotation marks and proper formatting.
Selector Mismatch
Ensure the selector configured on your mail server matches exactly what's in your DNS record. Even minor discrepancies cause failures.
Key Length Incompatibility
Modern security standards recommend 2048-bit keys. If you're using an older system, verify it supports your chosen key length.
DNS Propagation Delays
After making DNS changes, allow several hours for propagation before testing. Changes don't take effect instantly across all nameservers.
DKIM is just one piece of the puzzle
AutoSPF handles SPF flattening so your DKIM and DMARC alignment stays intact. Start your free trial today.
What Our Customers Say
"AutoSPF Flattens SPF Records Seamlessly & Keeps Changes Logged - I am quite pleased with the product"
It does what it promises to do, and does it very well. I appreciate that it keeps a log of changes made, which prevents many mistakes. A client's SPF record would have way too many lookups, but AutoSPF makes that problem go away. The length of the SPF record is typically not the issue; it's the amount of lookups in the record that are. AutoSPF "flattens" the record, automatically expanding the defined lookups to IP addresses or ranges. And it auto-updates the record when the un-flattened lookups change.
Peter J.
President · Small-Business (50 or fewer emp.)
"Helped us go beyond capacity"
AutoSPF did exactly as described, it helped us get past our 10 lookup limit. Afterwards, we hit another limit regarding overall capacity and when contacted, they quickly provided us with a new solution to eliminate capacity issues entirely going forward, so now we can add as many SPF records as needed. They also provided us with a personalized support video explaining their new method in its entirety using our instance as the example.
Verified User
Financial Services · Mid-Market (51-1000 emp.)