Choose one thing to test
A/B tests are most useful when the audience is similar and only one variable changes.


Good test variables
- Subject line.
- First sentence.
- Call to action.
- Proof point or offer.
Avoid false winners
- Do not change subject, offer, and CTA in the same test.
- Do not call a winner after a tiny sample.
- Compare reply or meeting rate, not only open rate.
- Archive the losing variant with notes so the team learns over time.
