Using numbers in email subject lines is one of the most attention-grabbing elements, because it's the first thing people will notice, and they'll want to discover what's behind those numbers.
Adding numbers to your email marketing subject lines not twitter database only makes them more compelling, but it also increases audience engagement.
Be careful: adding numbers can sometimes be counterproductive if you don't know how to handle them well. When you use very high numbers, you force the reader to stop and absorb the information, and this has the opposite effect.
If you leverage this element, numbers can be an opportunity to leverage your brand's credibility and trust. Here are some phrases you can use in your emails:
“13 Tech Purchases Your Kids Will Love.”
“When you open this email you will find 3 discount coupons.”
“Get a FREE course (valued at $100).”