Stax

Email Subject Line Generator

Generate 10 email subject lines for any goal.

Write subject lines that get emails opened

Your subject line determines whether your email gets opened or ignored. This generator creates purpose-built subject lines for each email type — from re-engagement campaigns to product launches — using the patterns that consistently earn high open rates.

Character count and spam word detection built in

Every generated subject line shows its character count with colour-coded guidance for optimal length, and flags words that can trigger spam filters — so you can fix issues before you hit send.

Frequently asked questions

How do I generate email subject lines?
Enter your topic or product name, optionally add your brand or sender name, select the email goal (newsletter, sales, announcement, etc.), and click Generate. You get 10 subject lines tailored to that goal.
What is a good email subject line length?
Under 60 characters shows fully on most email clients and mobile devices. The character count is colour-coded: green (≤60) is ideal, amber (61–70) is acceptable, and red (70+) may get cut off. Most email clients show 40–50 characters on mobile.
Why is my subject line flagged with a warning?
The warning appears when the subject line contains common spam-trigger words like FREE, URGENT, ACT NOW, or GUARANTEE. These words can reduce deliverability and send your email to the spam folder. Rephrase using benefit-focused language instead.
What subject line style gets the highest open rates?
Questions, curiosity gaps, and personalisation consistently outperform generic announcements. For sales emails, urgency works well but must be genuine. For newsletters, specificity beats vague teases — 'Your 3-step morning routine guide' beats 'This week's newsletter'.
Should I use emoji in email subject lines?
One relevant emoji can increase open rates when used sparingly — it adds visual differentiation in a crowded inbox. Overusing emoji or using them for every email trains your audience to ignore them. Test with a small segment before applying to your full list.

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