<b>Subject-line research worth more than a swipe file</b>

<b>Subject-line research worth more than a swipe file</b>
Studies, not listicles. Here's what actually moved numbers in published data.

🧪 Tests
— Litmus 'State of Email' subject-line section — confirms personalization-in-subject lifts opens modestly but tanks deliverability if it screams 'merge tag.' Read for the caveat, not the headline.
— Yes Lifecycle / Wunderkind length studies — the 'short subjects win' claim only holds for mobile-heavy lists; B2B lists invert it.
— Brevo's emoji A/B archive — emoji in subjects helps in retail, hurts in finance/affiliate. Audience, not aesthetic.
— GetResponse benchmark report — gives open-rate floors by industry so you stop comparing yourself to the wrong vertical.

These made it because they show ranges and conditions instead of one magic word.

Saved you ~2 hours of mistaking anecdotes for evidence.