I asked Claude to analyze 3,016 subject lines

Last week, I fed Claude every email I received in March.

3,016 subject lines.

I shared some surface-level findings on LinkedIn, but here's everything I actually found interesting.

45% of emails come from creators

The inbox is splitting into two games. DTC brands lean on urgency and launches:

Creators go first person:

SaaS barely shows up (22% of the emails I got last month), and when it does, it's boring product updates. If you're in SaaS and you're sending emails, this is who you're competing against.

42% of subject lines are under 30 characters

And 14% are just 1-3 words. "POV." "Tomorrow." "Greg said."

It's not that short performs better (that depends on a million things). It's that short usually signals confidence. You trust the reader to be curious enough to open.

20% use ALL CAPS, and only 2% use emojis

That surprised me. Caps are doing what emojis used to do, creating visual contrast in a wall of text to stand out in the inbox. But they feel less "marketer-y." "NEW on YouTube" reads differently than "🎬 New on YouTube." One feels like a person, the other feels like a brand.

1/4 subject lines use "you" or "your"

The rest talk about the product. Look at the difference:

"NEW Cloud Fill Collection is NOW LIVE!" → about the brand

"Are you waking up with back pain?" → about the reader

"Spring Break Sale Starts NOW!" → about the brand

"What season are you in?" → about the reader

I got all these in the same week. Which ones would you open?

After looking at 3,016 subject lines in one sitting, the real insight is simple: most emails look and sound exactly the same. The ones that stood out weren't the cleverest. They felt like someone had written them for a reason.

That's it. Short one this time. Thanks for reading!

David ✌️

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