Over the past few months, major LLMs like Anthropic’s Claude 3.5 Sonnet, Claude 3.7 Sonnet, and ChatGPT-4.5 have significantly improved in writing quality.

But with so many options available, which AI is the best for email copywriting?

To find out, we conducted an experiment that evaluated how different LLMs and AI-powered writing assistants produce marketing email copy. Click the button below to view the report (and the results!):

Note: This report was published on Tuesday, May 13th, 2025. Any new models or AI advancements after this date are not included in our testing!

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