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Tools / Subject & inbox / Subject line bank
Free tool

Email subject line bank

50+ subject line ideas across every kind of email. Fill in your brand once and they all become yours — then favourite the best and test them before you send. All in your browser.

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How to use the subject line bank

Fill in your brand, product or offer at the top and every line updates to fit you — that's the "switch out words" part. Browse by category or search, tap the heart to favourite the ones you like (they're saved on your device), copy any line, or hit Test to score it in the subject line tester before you send.

What makes these work

Every line here follows a proven pattern — curiosity, a clear benefit, a reason to act now, or a personal touch — kept short enough to survive the mobile inbox. They're starting points, not scripts: the best subject line is the one that sounds like you, so treat these as a springboard and make them yours.

Once you've picked one, run the whole email through the Mailfois pre-send checker — subject, links, deliverability and inbox preview in one score.

Found your line? Check the whole email.

Open the pre-send checker