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Module 7 · Lesson 22 of 37

HTML Email Coding

Part of The Complete Email Deliverability Course — Email Content Best Practices.

Key rules for cross-client compatibility:

  • 📐 Use table-based layouts (flexbox/grid aren't reliable)
  • 🎨 Apply inline CSS (many clients strip <style> blocks)
  • 📏 Keep total size under 102KB (Gmail clips larger messages)
  • 📝 Include plain text alternatives via MIME multipart

Gmail clips messages exceeding 102KB with a "View entire message" link, which breaks tracking and CTAs.

Some spam filters penalize HTML-only messages — always include a meaningful plain text version.

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