Free Tool

AI Email Subject Line Generator

Turn any email into open-worthy subject lines — curiosity, urgency, professional, and friendly angles, each with a matching preview text, instantly and in your browser.

Instant ideas Runs in your browser Preview text included

Your email subject lines will appear here. Pick a purpose and click Generate subject lines.

Generating ideas…

Subject lines

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How to write email subject lines that get opened

Your subject line — paired with the preview text — is the only thing standing between your email and the trash. Strong subject lines are short, specific, and give one clear reason to open. This generator gives you four proven angles plus a matching preview line for each, so you can A/B test what resonates with your list.

The four subject line angles

Curiosity — opens a loop the reader needs to close. Great for newsletters and content.
Urgency — adds a deadline or scarcity to drive action. Best for offers and launches.
Professional — clear, no-fluff value. Ideal for B2B and announcements.
Friendly — warm and personal, like a note from a colleague.

Tips for better results

Keep subject lines under ~55 characters so they don't get cut off on mobile.
Make the preview text continue the subject — don't repeat it.
Pick one line, then tweak it in your own voice — these are starting points, not final copy.

Pair this with your favourite email platform's A/B test feature to find the winning combination before you send to your full list.

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