Je kürzer der Betreff, umso höher die Öffnungs- und Klickraten!

Email newsletters with short subject lines (4-15 characters) had the highest average open rate (15.8%) last year, according to MailerMailer's annual Email Marketing Metrics Report.

Longer subject lines resulted in lower open rates, with a very slight correlation between length and open rate.

Click rates also peaked when subject lines were kept short. Subject lines of four to 15 characters had the highest click rate (2.6%). Very long subject lines—over 51 characters—had the lowest click rate (1.6%)...