Free Email Subject Line Generator
Create high-converting email subject lines in seconds. Get 10 optimized subject lines with character counts and predicted open rates.
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Tips for High-Converting Email Subject Lines
Keep It Under 50 Characters
Subject lines under 50 characters have higher open rates. Most mobile devices truncate at 35-40 characters, so front-load the important words.
Use Numbers and Data
Subject lines with numbers get 45% higher open rates. Be specific: "5 Tips" performs better than "Several Tips" because numbers set clear expectations.
Create Curiosity Gaps
Tease the content without giving everything away. Phrases like "The mistake most marketers make..." create an irresistible urge to open and learn more.
Personalize When Possible
Emails with personalized subject lines are 26% more likely to be opened. Use the recipient's name, company, or reference their specific situation.
Avoid Spam Triggers
Stay away from ALL CAPS, excessive exclamation marks, and words like "FREE!!!" or "Act Now!!!" These trigger spam filters and reduce deliverability.
A/B Test Everything
Even small changes can impact open rates significantly. Test different approaches: questions vs. statements, short vs. long, with emoji vs. without.
Frequently Asked Questions
What is the ideal email subject line length?
The ideal email subject line length is between 30 and 50 characters. Subject lines in this range tend to have the highest open rates. Mobile devices typically show 35-40 characters, so keep your most important words at the beginning. Our generator color-codes character counts: green for under 50 characters (optimal), yellow for 50-60 (acceptable), and red for over 60 (too long).
How many subject lines can I generate for free?
You can generate 5 sets of subject lines per day (each set contains 10 unique subject line variants in different styles). Upgrade to Premium for unlimited subject line generation.
What do the open rate predictions mean?
The open rate predictions (High, Medium, Low) are estimates based on proven email marketing factors: subject line length, use of power words, personalization tokens, numbers, and questions. These are not guarantees but based on industry research about what drives higher open rates.
What are power words in email subject lines?
Power words are emotionally charged words that trigger a psychological response and compel recipients to open the email. Examples include "exclusive," "urgent," "proven," "secret," "free," and "discover." Our generator strategically incorporates power words to maximize engagement.
Should I use emojis in email subject lines?
Emojis can increase open rates by up to 56% when used appropriately. They help your email stand out in a crowded inbox. However, use them sparingly (1-2 max) and ensure they are relevant to your content. Not all email clients render emojis the same way, so always test.
How do I avoid spam filters with my subject lines?
Avoid ALL CAPS, excessive punctuation (!!!), and known spam trigger words like "buy now," "free gift," or "no obligation." Keep your subject line honest and relevant to the email content. Misleading subject lines not only trigger spam filters but also violate CAN-SPAM regulations.