The patterns in your top 20 subject lines all-time are the closest thing you have to a formula for your specific audience. This prompt finds them, extracts the rules, and hands you a framework to use forever.
Every email list has a subject line fingerprint. The phrasing, tone, structure, and length that makes one audience open consistently is different from what moves another. Most email advice gives you someone else's fingerprint. Your data holds your own.
After months or years of sending, your highest-performing subject lines have been sitting in your Kit account accumulating as a pattern library that no one has ever looked at as a whole. This prompt changes that.
You will leave this conversation with a documented subject line framework built entirely on what has worked for your specific audience, in your specific voice, over your specific history. It cannot be copied because it came from you.
Paste the prompt below into Claude with your Kit connector active.
Pull my top 20 Kit broadcasts by open rate of all time. List each subject line along with its open rate and send date. Then analyze the 20 subject lines as a group: What length do most of them share? What structural patterns do you see (questions, numbers, statements, curiosity gaps, specific claims)? What tone or voice characteristics show up repeatedly? Based on this analysis, write a three-to-five rule subject line formula I can use going forward.
Claude will return a breakdown of what your top 20 subject lines have in common. Some patterns will be obvious once you see them. Others will surprise you. Read the analysis twice before moving to the formula.
Claude will distill the patterns into a three-to-five rule formula specific to your data. This is not generic advice. It is built from your actual performance history. Save it somewhere you will see it every time you write a new subject line.
Apply at least two rules from your formula to each of your next five broadcasts and track whether the open rates hold above your historical average. You are testing whether the pattern is durable or whether it was tied to a specific moment in time.
Run this prompt again every six months and add the new top performers to the analysis. Subject line preferences drift as your audience evolves and your list grows. The formula should drift with it.
A subject line formula built from your own data is the most durable writing tool you can have. It improves every time you use it and gets more accurate the longer your list exists. Run this once and you will have a framework that compounds for years.
Free Download
Your future self will thank you for saving this.
Follow along for the next guide
New free guide every Tuesday. Find them first on Instagram, TikTok, or by subscribing to the email list. Pick your favorite way to stay close.
Want more?
One new free guide. Every Tuesday. No spam, no fluff, just the systems and prompts I'm building for clients, simplified for you.
Subscribe