AI-Powered Email
Subject Line Generator
Craft compelling email subject lines that drive opens. Our AI analyzes your message intent, audience stage, and tone to generate high-converting subject lines in seconds.
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Generated Subject Lines
Click to copyPowered by AI • Free email marketing tool by Octeth
Your Subject Line Determines 47% of Email Opens
The subject line is the first—and often only—impression your email makes. Research shows that 47% of recipients decide whether to open an email based solely on the subject line. Meanwhile, 69% mark emails as spam based on the subject line alone.
Save Hours of Work
Stop staring at a blank screen. Get multiple professionally crafted options in seconds.
Increase Open Rates
Subject lines optimized using engagement data and proven copywriting formulas.
Match Any Campaign
From product launches to newsletters—get subject lines tailored to your specific email type.
Generate Subject Lines Backed by Data Science
Our AI email subject line generator analyzes thousands of high-performing email campaigns to understand what drives opens.
Audience-Aware
Tailored suggestions based on whether you're targeting awareness, acquisition, engagement, sales, or retention stages.
Tone Matching
From formal business communications to conversational newsletters—match your brand voice perfectly.
Intent-Driven
Options designed to spark curiosity, prompt action, or engage with questions—based on your goals.
Multi-Language
Support for 15 languages including English, Spanish, French, German, Japanese, and more.
Email Subject Line Best Practices
Follow these proven strategies to maximize your email open rates alongside AI-generated subject lines.
Keep It Concise
Subject lines with 6-10 words typically perform best. Mobile devices truncate longer subjects, hiding your key message.
Create Urgency (Smartly)
Words like "limited," "today," and "exclusive" drive action—but avoid ALL CAPS and excessive punctuation that trigger spam filters.
Personalize When Possible
Emails with personalized subject lines are 26% more likely to be opened. Include relevant details that resonate with your audience.
Test and Iterate
A/B test different subject lines to understand what resonates with your specific audience. Use data to refine your approach.
Frequently Asked Questions
How does the AI generate subject lines?
Our AI analyzes your email description, audience stage, tone preferences, and intent to generate contextually relevant subject lines using advanced language models trained on high-performing email campaigns.
How many subject lines will I receive?
Each generation produces multiple subject line options, giving you variety to choose from or A/B test. You can generate additional options by clicking "Generate More Subject Lines."
Can I use emojis in my subject lines?
Yes! Toggle the "Include Emoji" option to receive subject lines with relevant emojis. Emojis can increase open rates by up to 56% when used appropriately for your audience and brand.
What languages are supported?
We support 15 languages: English, Spanish, Mandarin, French, Arabic, Portuguese, Russian, Japanese, German, Italian, Hindi, Turkish, Korean, Dutch, and Greek.
Is there a limit to how many subject lines I can generate?
The free tool has a limit of 10 generations per hour to ensure fair access for all users. For unlimited generation and more advanced email marketing features, explore our email marketing platform.
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