How it works
Under 50 characters
Phone inboxes cut long subjects. Put the important words first.
Use the preview text
The line after the subject is free space. Add the detail the subject leaves out.
Test two versions
Send two subjects to small groups and use the one with more opens for the rest of the list.
Frequently asked questions
How long should an email subject line be?
Under about 50 characters, and the first 30 should make sense alone, since phones show less.
Do emojis help open rates?
Sometimes. Use at most one, and test it. Too many can look like spam.
What words should I avoid?
Avoid ALL CAPS, lots of exclamation marks and pushy phrases like “act now”. They can hurt deliverability.