List Building
Email Test Sample Size: The Real Math
Most email A/B tests cannot detect the difference they report finding. Here is the arithmetic, and what to do when your list is too small for it.
Oct 15, 20265 min read
Tag
#A/B testing
8 articles tagged with A/B testing.
List Building
Email A/B Testing You Can Trust
Most email A/B tests are too small to detect the difference they claim to have found. Here is how to run tests whose results you can actually act on.
Oct 9, 20265 min read
AI Email Marketing
How to Use an AI Subject Line Generator
An AI subject line generator is worth using for the same reason a thesaurus is: it gives you options you would not have reached. Here is how to get useful ones.
Sep 18, 20265 min read
Metrics & Benchmarks
How to A/B Test Emails Properly
Most email A/B tests are not tests — they are noise read as signal. This guide covers writing a real hypothesis, choosing variables by impact, splitting the list correctly, the sample sizes needed to detect a given difference, why open rate is the wrong success metric, and how to build a testing program instead of a testing habit.
Sep 18, 20269 min read
Email Copywriting
Emoji in Subject Lines: Help or Hurt?
Emoji do not trigger spam filters on their own — but they do break across clients, eat mobile preview characters, and get read aloud by screen readers. Here is when they help, when they clearly hurt, how to test them honestly, and a style guide you can adopt today.
Sep 4, 20268 min read
Email Copywriting
Clever Email Subject Lines (and Why They Work)
Clever email subject lines work because they combine curiosity, specificity, and relevance — then pay off the promise inside the email. Here are the five mechanics behind lines that get opened, twelve annotated examples you can adapt, formatting rules that quietly change performance, and a testing workflow that replaces guessing with evidence.
Aug 9, 20268 min read
Email Copywriting
How to Write Email CTAs That Get Clicks
A practical guide to writing email CTAs that actually get clicked: name the outcome instead of the mechanic, place the button where motivation peaks, and ask for one thing only. Includes a weak-vs-strong CTA rewrite table, placement rules by email type, button design specs, reassurance microcopy, and a testing method that produces reusable lessons.
Aug 6, 20268 min read
Email Copywriting
Email Subject Line Best Practices: A Checklist
A practical, no-fluff checklist for writing email subject lines that get opened: length limits, formulas that still work, when personalization helps or hurts, how to handle emojis and punctuation, and how to A/B test without fooling yourself.
Aug 4, 20268 min read