Authenticate Every Email You Send with a DKIM Record
Stop emails from landing in spam and protect your sender reputation with a properly configured DKIM signature.
A DKIM record is a cryptographic signature added to your outgoing email headers that proves the message hasn't been tampered with and was actually sent by your domain. Without one, email providers like Gmail and Outlook are more likely to mark your messages as spam or reject them outright. Setting up a DKIM record is a critical step in email authentication, alongside SPF and DMARC.
Deliverability toolkit
Generate SPF and DMARC records and scan text for spam-trigger words.
One-Click DKIM Generator
Emailer automatically creates a 2048-bit RSA key pair for your domain, producing a ready-to-publish TXT record. No manual cryptography or complex commands.
Real-Time DKIM Verification
After you add the TXT record to your DNS, Emailer instantly checks if the record is correctly published and signed. You get a green checkmark when it's live.
Multi-Selector Support
Manage multiple DKIM selectors for different sending streams or services without conflict. Rotate keys easily to maintain security best practices.
What Is a DKIM Record and Why Do You Need One?
DKIM (DomainKeys Identified Mail) adds a digital signature to every email you send. This signature is generated using a private key stored on your email server, and a matching public key published in your DNS as a TXT record. Receiving mail servers use the public key to verify the signature, confirming the email is authentic and hasn't been altered in transit.
Without a DKIM record, attackers can forge your domain to send phishing emails. A valid DKIM record greatly reduces the chance of your legitimate emails being flagged as spam. Most major email providers now require DKIM for optimal deliverability.
How to Generate a DKIM Record for Your Domain
Most email service providers, including Emailer, include a DKIM generator that creates the necessary key pair for you. To generate a DKIM record, log into your email platform, navigate to the authentication or DNS settings, and select your sending domain. The tool will automatically create a 2048-bit RSA key pair and output the values you need to add to your DNS.
The generated DKIM record typically looks like a long string of alphanumeric characters with a selector name (e.g., ‘default’ or ‘emailer’). You copy the TXT record value exactly as provided and paste it into your domain's DNS management console under ‘TXT records’ with the proper hostname (e.g., default._domainkey.yourdomain.com).
Step-by-Step Guide: DKIM Setup for Emailer Users
1. Go to the Emailer dashboard and click on ‘Settings’ > ‘Sending Domains’. If your domain isn't verified, complete the SPF and domain verification first. 2. Click ‘Generate DKIM Record’ – Emailer will create a unique private and public key pair. 3. Copy the TXT record that appears. It includes the selector (e.g., “emailer”) and the long public key value. 4. Log into your domain registrar or DNS hosting provider (e.g., Cloudflare, GoDaddy, Namecheap) and add a new TXT record. The host is usually “emailer._domainkey” (replace “emailer” with your selector). The value is the public key string. Save and wait for DNS propagation (up to 48 hours, but often under an hour). 5. Return to Emailer and click ‘Verify DKIM’. Once it shows “verified”, you're ready to send authenticated emails.
If propagation hasn't completed, you can retry verification later. After successful DKIM setup, your emails will carry a digital signature that major inbox providers trust, dramatically improving deliverability.
Common DKIM Setup Mistakes and How to Avoid Them
One frequent mistake is copying the DKIM record incorrectly – ensure you include the full value, including any quotes or trailing spaces. Another mistake is using the wrong selector hostname; each platform gives you a specific selector, and you must match it exactly. Also, never use the same DKIM key for multiple services – use a unique selector for each email provider to maintain security and allow easy key rotation.
If your DKIM setup passes validation but emails still go to spam, check that your SPF record is also correct. DKIM alone isn't enough; a full authentication stack (SPF + DKIM + DMARC) provides the best protection. Use Emailer's built-in diagnostic tools to test your record before sending important campaigns.
Transactional Email Deliverability
E-commerce stores and SaaS platforms sending order confirmations, password resets, and receipts need DKIM to ensure these critical emails reach the inbox. Emailer's DKIM setup reduces bounce rates and spam complaints.
Marketing Campaign Authentication
When you send newsletters or promotional emails, a valid DKIM signature signals to Gmail and Outlook that you're a legitimate sender. This protects your domain reputation and improves open rates.
B2B Communication Trust
Corporate email systems often quarantine or reject unsigned emails. With DKIM, your business proposals, reports, and follow-ups are authenticated, building trust with partners and clients.
FAQ
What is a DKIM record exactly?
A DKIM record is a DNS TXT record that contains a public key. Mail servers use this key to verify the digital signature attached to your outgoing emails, ensuring they haven't been forged or altered.
How long does it take for a DKIM record to propagate?
DNS propagation can take anywhere from 5 minutes to 48 hours. Most changes are effective within an hour. Use Emailer's verification tool to check propagation status.
Can I have multiple DKIM records for the same domain?
Yes, you can have multiple DKIM records using different selectors (e.g., s1._domainkey, s2._domainkey). Each selector points to a different public key, allowing you to use different email providers or rotate keys.
What's the difference between DKIM, SPF, and DMARC?
SPF authorizes which IPs can send email for your domain. DKIM adds a cryptographic signature. DMARC tells inbox providers how to handle emails that fail SPF or DKIM. All three work together for best deliverability.
Do I need a DKIM record if I only send a few emails per month?
Yes. Even low-volume senders benefit from DKIM. Many email providers treat unsigned emails with more suspicion. A DKIM record helps protect your domain from being spoofed and ensures your few emails land in the inbox.
Get Your DKIM Record Set Up in Minutes
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