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Newsletter Subject Line Checker
These are the same rules lightbreak uses to write subject lines for 20+ local newsletters. Every check runs in your browser.
Every check runs in your browser. Nothing you type is sent anywhere.
What makes a good local newsletter subject line?
A good local newsletter subject line starts with one fitting emoji, runs about 50 characters, and leads with one specific thing: a name, a place or a number. It opens a question the email answers. The preview text starts with "Plus:" and names about three other stories. Skip exclamation points, dates and phrases like "Don't miss".
Want Claude to do this for you? The free Subject Line and Preview Text Writer skill uses the same rules and does the whole job, not just the check.
lightbreak writes the subject line, preview text and the whole issue for you, using these rules.
See lightbreakQuestions
How long should a newsletter subject line be?
About 50 characters and 6 to 9 words, with a hard cap of 72. The hook has to land in the first 40 characters, because that is what most phones show.
Should I use emoji in subject lines?
Use exactly one, at the very start, and make it fit the lead story. One emoji helps the line stand out in an inbox; several look like spam.
What should preview text say?
Start with "Plus:" or "Also inside:" and list about three other items from the issue, in roughly 100 characters. Don't repeat the subject line's story.