Email Authentication: Setting Up SPF and DKIM for Your Newsletters

Mastering Email Authentication: Essential Steps to Protect Your Domain and Boost Deliverability

Email Authentication: Setting Up SPF and DKIM for Your NewslettersBefore you hit send on that next email campaign, remember that email authentication is your first line of defense.

It’s not just about keeping your emails out of the spam folder, email authentication protects your reputation and ensures your emails are seen by your audience.

With recent updates from Google and Yahoo, it’s clear that taking a proactive stance on email authentication is a must. At the core of this are two key tools every email sender should be using: SPF and DKIM.

Let’s break down what SPF and DKIM actually do, how they safeguard your sending domain, and how you can set them up for your newsletters.

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Why SPF and DKIM Matter

Sender Policy Framework (SPF) has been essential for email authentication since 2004. SPF lets you define which email platforms and IP addresses are authorized to send mail on behalf of your domain. This means you can send emails from various sources like:

  • An email service provider, like Beehiiv or ConvertKit
  • A mailbox, like Gmail or Outlook
  • Third-party tools, like Shopify or Stripe

By specifying these sources, you help reduce spam and prevent email spoofing.

DomainKeys Identified Mail (DKIM) is another crucial tool that emerged in 2004. DKIM allows you to add a cryptographic signature to your email headers, verifying that the email hasn’t been tampered with and that it genuinely comes from your domain. Setting up DKIM involves adding a digital signature to your email messages, which is then verified against a public cryptographic key published in your DNS.

A properly configured DKIM record not only secures your emails but also boosts deliverability. Email service providers are more likely to trust and deliver emails that can prove their authenticity, reducing the chances of your messages being flagged as spam.

Integrating SPF and DKIM in Your Email Authentication Strategy

Knowing how to authenticate email correctly involves updating your DNS records to include SPF and DKIM settings for all the email sources you use. This ensures that emails sent from your domain or subdomains are recognized as legitimate, enhancing deliverability and protecting your brand’s reputation.

SPF Setup

Start by consolidating all your sending sources into a single SPF record to avoid exceeding DNS lookup limits and ensure comprehensive coverage.

For instance, if you use Google Workspace, your SPF record might look like this:

v=spf1 ~all

Remember, you can only have one SPF record per domain or subdomain. If you need to add another source, like an email marketing platform, you’ll need to merge them:

v=spf1 ~all

Keep in mind the DNS lookup limit — you’re allowed only 10 lookups. Regularly check your SPF records to remove any unused sources, ensuring you stay within the limit and maintain effective email deliverability.

DKIM Configuration

Publish a DKIM record for each sending domain or subdomain with every tool you use. These records usually look something like this:


How to Check Your SPF and DKIM Settings

Verifying your SPF and DKIM setup is straightforward. For Gmail users, follow these steps:

  1. Send yourself a test email and open it in your Gmail inbox.
  2. Select the three dots in the email’s upper-right corner to access more options.
  3. Choose “Show Original” to view the email’s detailed headers and authentication results.
  4. Look for the PASS status next to SPF and DKIM. If both show PASS, you’re good to go. If not, you’ll need to fix the errors.

Tools like AboutMy.Email can also help verify your email authentication. Send a test email to their system, and within a minute, it’ll identify any authentication errors.

How to Authenticate Email: Beyond SPF and DKIM

SPF and DKIM are fundamental for safeguarding your sender reputation and ensuring your emails reach the inbox. But don’t stop there. 

  • Set up DMARC: This helps protect your domain from being used for phishing and other malicious activities.
  • Keep your email lists clean: Regularly remove inactive subscribers and maintain engagement with your audience.
  • Monitor your spam complaint rates: Tools like Google Postmaster can help you track and manage spam complaints.

By understanding how to authenticate email, you’ll not only protect your domain but also improve your overall email deliverability. Remember, a secure email strategy is key to maintaining effective communication and protecting your brand.

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