For Marketing Teams

Your latest campaign has great copy, perfect timing, and a compelling offer. But none of that matters if your emails land in spam folders—or don't arrive at all.

DKIM authentication is the difference between emails that reach the inbox and emails that disappear. For marketing teams, getting DKIM right directly impacts campaign performance and ROI.

The Marketing Team Problem

Email marketing has gotten harder. ISPs like Gmail and Yahoo have tightened their spam filters. In 2024, they started requiring DKIM authentication for bulk senders—anyone sending more than 5,000 emails per day.

Without proper DKIM:

Your open rates drop because emails go to spam
Your sender reputation suffers
Your domain can get blacklisted
Campaign ROI plummets

Email providers don't just check if DKIM is present—they check if it's configured correctly. A misconfigured DKIM record can be worse than no DKIM at all.

How DKIM Testing Helps Marketing Teams

Verify before you send

Test your DKIM configuration before launching campaigns. Catch issues when they're easy to fix, not after emails have bounced.

Monitor multiple sending services

Using Mailchimp, HubSpot, and Salesforce? Each needs its own DKIM setup. Keep track of all your selectors and verify they're working.

Protect your sender reputation

DKIM failures hurt your domain reputation. Regular testing catches problems before they accumulate damage.

Debug deliverability issues

When campaign performance drops, DKIM testing helps you rule out (or identify) authentication as the cause.

Common Marketing Email Scenarios

Scenario 1: Multiple Email Services

Most marketing teams use multiple platforms—one for newsletters, another for transactional emails, maybe a CRM for sales sequences.

Each service needs its own DKIM configuration:

Platform	Typical Selector	What to Check
Mailchimp	k1, k2, k3	Domain authentication in Settings
HubSpot	hs1, hs2	Email settings → Domain authentication
Klaviyo	kl, kl2	Account → Domains → Sending domains
SendGrid	s1, s2	Settings → Sender Authentication

Test each selector to ensure all your sending paths are authenticated.

Scenario 2: New Domain or Subdomain

Launching campaigns from a new domain or marketing.yourdomain.com? DKIM needs to be set up for the new sending domain.

Generate DKIM for the new domain

Configure DKIM in your email service for the new sending domain.

Add DNS records

Add the TXT records to your new domain's DNS.

Wait for propagation

DNS changes can take up to 48 hours (usually much faster).

Test before sending

Verify the DKIM record resolves correctly before launching campaigns.

Scenario 3: Sudden Deliverability Drop

Open rates tanked overnight? DKIM might be the culprit. Common causes:

DNS records were accidentally deleted or modified
Your email service rotated keys and you didn't update DNS
IT made changes without realizing the impact
Your domain's DNS provider had issues

Test your DKIM immediately when you see unexplained deliverability drops.

What to Check Regularly

As a marketing team, add these to your pre-campaign checklist:

Before every major campaign:

Test DKIM for your primary sending domain
Verify all email services you're using have valid DKIM

Monthly:

Check DKIM for all your sending domains and subdomains
Review any domains you've added to your email stack
Confirm nothing has changed in your DNS

When switching providers:

Set up DKIM for the new service before migrating
Keep old DKIM records active until migration is complete
Test both old and new configurations during transition

Pro tip

Keep a spreadsheet of all your sending domains, email services, and DKIM selectors. Update it whenever you add or change a service. This makes troubleshooting much faster.

Beyond DKIM: The Full Authentication Stack

DKIM is essential, but it's one piece of email authentication. For best deliverability:

SPF: Lists which servers can send email for your domain. Check at spfrecordcheck.com.

DMARC: Tells receiving servers what to do when authentication fails. Check at dmarcrecordchecker.com.

MX Records: Ensures your domain can receive email (including bounces). Check at mxrecordchecker.com.

All four should be configured and monitored for reliable email delivery.

Monitor Your DKIM Records

Checking once is good. Monitoring continuously is better. The Email Deliverability Suite watches your SPF, DKIM, DMARC, and MX records daily and alerts you when something breaks.

Never miss a DKIM issue

Monitor your SPF, DKIM, DMARC and MX records daily. Get alerts when something breaks.

Start Monitoring

DKIM Testing for Marketing Teams