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 common spam trigger patterns and formatting risks.

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.

Email Subject Line Tester

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