DKIM Record Generator

DKIM (DomainKeys Identified Mail) is an email authentication method that adds a digital signature to your outgoing emails. This signature is embedded in the email header and is secured with cryptography.

When a receiving mail server gets your email, it checks your DNS records for a public key that matches the signature. This process confirms that the email genuinely came from your domain and that its contents weren't altered in transit. For cold outbound, it's a non-negotiable part of proving your sending infrastructure is legitimate.

For teams sending thousands of emails, DKIM isn't just a technical detail—it's a core component of deliverability. Ignoring it is like trying to build a house without a foundation.

1. Builds Trust with ISPs: Inbox providers like Google and Microsoft use DKIM as a primary signal to verify your identity. A valid signature tells them you are who you say you are, which is the first step to getting out of the spam folder.
2. Protects Domain Reputation: DKIM prevents bad actors from spoofing your domain. Without it, anyone could send malicious emails that look like they came from you, destroying your domain's reputation and getting you blacklisted.
3. Improves Deliverability: A missing or failed DKIM check is a major red flag for spam filters. Passing DKIM, along with SPF and DMARC, significantly increases the likelihood that your emails will land in the primary inbox.

Setting up DKIM involves adding a specific record to your domain's DNS settings. It seems complex, but it's a straightforward process once you understand the components.

1. Generate the Record from Your Sending Provider: You don't create the DKIM key yourself. Your email service provider (e.g., Google Workspace, SuperSend, SendGrid) will generate a unique key pair for you. You'll be given a selector and a value to publish in your DNS.
2. Use the Correct Selector: The DKIM record name isn't just _domainkey. It includes a unique selector, like google._domainkey or s1._domainkey. This selector tells the receiving server which public key to look for, allowing you to have multiple DKIM records for different sending services.
3. Publish as a TXT Record: In your DNS provider (like GoDaddy, Cloudflare, or Namecheap), create a new TXT record. The Host/Name will be the selector (e.g., google._domainkey), and the Value/Content will be the long string of characters provided by your email platform.
4. Verify Before Sending: Don't just set it and forget it. Use a tool like MXToolbox or mail-tester.com to verify that the record is published correctly and can be read publicly. Wait for DNS propagation (this can take anywhere from a few minutes to 48 hours) before you start a campaign.

A misconfigured DKIM record is often worse than having no record at all. Here are the most common failure points we see:

1. Copy-Paste Errors: The DKIM public key is a very long, unforgiving string of text. Accidentally adding a space, a line break, or missing a single character will cause the validation to fail. Always copy the full, raw value.
2. Incorrect Record Name: Forgetting the selector and just using _domainkey as the host name is a frequent mistake. The name must match exactly what your sending provider specifies.
3. DNS Provider Splitting the Key: Some DNS providers automatically split long TXT records into multiple strings. This can break the key. You may need to manually enclose the entire value in quotes ("...") to ensure it's treated as a single entry.

Ultimately, teams sending cold outbound at scale need to understand DKIM. It's not optional. Proper authentication is the foundation of a healthy sending infrastructure, directly impacting whether your domains, inboxes, and reply rates stay healthy or get burned.