Originally released in June 2008, Alchemy Worx’s study of over 600 subject lines across 200 million messages showed an unexpected relationship between click-to-open rates and subject line length, suggesting very strongly that past subject line analysis may have led email marketers seriously astray.
In order to provide insight into what subject lines work best, our deep analysis examined the data in a granular way and added an additional level of sophistication to previously released reports.