What makes a good email subject line?

A good subject line is 30-50 characters, creates curiosity or urgency, avoids spam trigger words, and is relevant to the email content. Personalization (using the recipient's name) can boost open rates by 20-30%.

What are spam trigger words?

Words like 'FREE', 'Act Now', 'Limited Time', 'Guaranteed', and excessive punctuation (!!! or ???) can trigger spam filters. Our tool checks for 100+ known spam trigger patterns.

What's the ideal subject line length?

41-50 characters is optimal for most email clients. Mobile devices show roughly 30-40 characters, so front-load important words. Subject lines over 60 characters get cut off on most devices.

Does emoji in subject lines help?

A single relevant emoji can increase open rates, but overusing emojis can trigger spam filters. One emoji at the start or end of the subject line is a safe approach.

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