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AI for Email Marketing Specialist

Use Mailchimp's Content Optimizer and Subject Line Helper

For Email Marketing Specialists

Tool: Mailchimp | AI Features: Content Optimizer, Subject Line Helper, Send Time Optimization | Time: 10 minutes to learn | Difficulty: Beginner

What This Does

Mailchimp's AI tools analyze your email content before you send it — comparing your subject lines, body copy, and send timing against data from billions of campaigns in the Mailchimp network. The Content Optimizer provides specific, actionable improvements (not just a score), and the Subject Line Helper generates and rates subject line variants before you commit to one.

Before You Start

  • Mailchimp account (Standard plan or above for full AI features)
  • A campaign drafted and ready to review (not yet sent)
  • At least a few months of campaign history for personalized recommendations

Feature 1: Subject Line Helper

Steps

  1. In the Mailchimp campaign editor, navigate to Subject in the campaign setup
  2. Type your subject line draft
  3. Click Subject line helper (appears below the subject line field)
  4. The panel shows:
    • Subject line rating (A-F scale based on Mailchimp's data)
    • Predicted open rate lift (vs. your account average)
    • Character count and emoji assessment
    • Suggestions for improvement (e.g., "Adding a number increases open rate for this audience")
  5. Optionally click Generate alternatives to see AI-generated subject line options
  6. Apply suggestions or use a generated alternative → re-run the helper to see the new rating

What you should see: A letter grade, predicted lift, and 2-3 specific improvement suggestions. A "C" grade subject line with a B-grade suggestion shown side-by-side makes the decision clear.

Feature 2: Content Optimizer

Steps

  1. After completing your email content, click Preview and test in the campaign checklist
  2. Scroll down to find Content Optimizer (or it may appear as a step in your campaign checklist)
  3. Click Run Content Optimizer
  4. Mailchimp analyzes your email across:
    • Images (image-to-text ratio, image sizes, alt text presence)
    • Personalization (are you using personalization tags? Are they set up correctly?)
    • Copy (reading level, paragraph length, CTA clarity)
    • Layout (single vs. multi-column for your audience type)
  5. Review the suggestions — each is tagged as High / Medium / Low impact
  6. Apply the high-impact suggestions before sending

Troubleshooting: The Content Optimizer may not appear for all account types or template styles. If it's not available, check Mailchimp's plan feature comparison or look under the Preview & Test menu.

Feature 3: Send Time Optimization

Steps

  1. On the Schedule step of your campaign
  2. Select Send at the best time instead of choosing a manual send time
  3. Mailchimp uses your account's open rate history (plus aggregate Mailchimp data) to choose the optimal send window
  4. Review the recommended send window → confirm schedule

Minimum data requirement: Mailchimp needs at least 200 contacts and 10 previous campaigns to generate reliable predictions. For new accounts, the recommendation is based on aggregate network data until your account history builds.

Real Example

Before Content Optimizer:

  • Subject line: "Our spring collection is here" — rated C+
  • Content: 4 images, 50 words of text — image-heavy warning flagged
  • CTA: "Click here" — low-specificity CTA flagged

After applying suggestions:

  • Subject line: "Spring is here — and so are 12 new arrivals" — rated B+
  • Added 30 words of product description text to improve image ratio
  • CTA changed to "See the Spring Collection" — specific and action-oriented

Result: Estimated 4% open rate improvement, 15% CTR improvement from more specific CTA.

Tips

  • Run the Subject Line Helper with your first instinct AND ask it to generate 3 alternatives — comparing your idea against the data-informed alternatives often reveals that your instinct was right, or surfaces a clearly better option
  • The Content Optimizer is not a rubber stamp — it surfaces issues but doesn't fix them. Reserve 15 minutes after running it to actually implement the high-impact suggestions
  • "High impact" suggestions always take priority over "medium" and "low." If you're short on time, do only the high-impact ones.

Mailchimp updates its AI features regularly and feature availability varies by plan. Look for AI-related features under Preview & Test or the campaign checklist sidebar.