I sent 847 cold emails as a developer-turned-freelancer. Here's the data.

Five years ago I sent my first cold email to a potential client.

It was terrible. I know because I got no reply — and I kept sending emails just like it for the next six months, wondering why nothing worked.

Then I started tracking.

Every subject line. Every open rate (when trackable). Every reply. Every follow-up. 847 emails total over 5 years of freelancing.

Here's what the data actually showed.

The counterintuitive findings

Short emails massively outperform long ones.

My emails under 100 words had a reply rate 3.2x higher than emails over 200 words. The reader shouldn't have to work. One problem, one idea, one ask.

Follow-up 2 and 3 are where the money is.

40% of my replies came on follow-up email 2 or 3. Most people give up after the first email. Don't.

Personalization doesn't mean "Hi [First Name]."

It means proving you actually looked at their business. One specific detail — a blog post they wrote, a product they just launched, a hire they made — is worth more than 500 words of generic flattery.

The best subject lines are boring.

My highest open rate (71%) came from: "[Their company] — quick thought on [specific thing I noticed]"

Not clever. Not mysterious. Just specific.

The opener that worked best

Over 200+ sends, this opener got a 31% reply rate:

"I noticed [specific thing about their business/content/problem]. Most [companies like theirs] deal with [consequence]. I had an idea that might help — mind if I share it in 2 sentences?"

That's it. No credentials. No portfolio link. No "I hope this finds you well."

What I built from this

I turned all 847 emails' worth of learning into a swipe file — 31 templates that consistently worked, each with open and reply rate data from real sends. Organized by use case: intro emails, follow-ups, referral requests, re-engagement of cold leads.

It's $27 at xmr2012.gumroad.com/l/vbrgjf

I also built two other products alongside it: