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Email Subject Line Generator
Create compelling email subject lines that get opened. AI-powered subject line creation.
Generating needs a PostNext account. New accounts start with a 7-day free trial that asks for a card; cancel before it ends to keep the free plan, which includes AI credits every month.
Subject Line Ideas
Multiple Variations
All Email Types
Step 1: Describe Your Email
Step 2: Select Options
Step 3: Generate
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Email Subject Line Generator FAQ
What makes a good email subject line?
Good subject lines are short, specific and clear about what the reader gets. Curiosity and personalization can help when they are honest. The generator gives you options to start from; your own open rates tell you which style works for your list.
How long should subject lines be?
Short ones are safer, because phones show only the first part of a subject line. Put the key words first, and check how it looks in your own inbox before you send.
Should I use emojis in subject lines?
Sometimes. An emoji can help a subject line stand out in a crowded inbox, but results vary by audience: B2C lists often accept them, B2B lists less so. Test with and without, and choose here whether to include them.
What is personalization in subject lines?
Personalization uses data like the recipient's name or company through tokens such as [First Name]. It helps when the data is accurate; a wrong name hurts more than none. The generator can include tokens ready for your email platform.
How do I avoid spam filters?
Avoid spam triggers like ALL CAPS, excessive punctuation (!!!), misleading claims and phrases like 'FREE!!!' or 'Act Now!!!', and keep your sender reputation healthy with clean email lists. No subject line can guarantee inbox placement: that also depends on your sending reputation and your list.
Should I A/B test subject lines?
Yes. A/B testing subject lines is how you learn what works for your list. Test one variable at a time, such as length, personalization, emojis or urgency. Generate several variations here, then run the test in your email tool: PostNext does not send email or run A/B tests.
What tone works best for emails?
The best email tone depends on your audience and campaign type. B2B emails typically perform better with professional, value-focused language, while B2C campaigns can use casual, urgent, or emotional tones. Our AI subject line generator offers multiple tone options including professional, friendly, urgent, and curious to match your brand voice.
Is there a limit to subject lines I can generate?
Each generation uses AI credits from your PostNext plan: 10 a month on the free plan, 150 on Premium and 500 on Business. Generating needs an account, and new accounts start with a 7-day free trial that asks for a card.