Score subject lines 0-100 with spam detection, power words, Gmail preview, and A/B comparison mode.
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Quick answers to common questions
Effective subject lines are 30-50 characters, create curiosity or urgency, use personalisation, avoid spam triggers, and are specific rather than vague.
30-50 characters perform best for desktop, under 30 for mobile. Very long subjects (60+) get cut off in previews.
Common triggers: FREE, GUARANTEED, WINNER, ACT NOW, excessive punctuation, and $ signs. Combinations increase spam score significantly.
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