Mimecast vs Rackspace Email

Mimecast is used by more websites in our catalog: 11,342 use Mimecast and 7,491 use Rackspace Email.

Mimecast sites have the higher median Ahrefs Domain Rating (Mimecast: 51, Rackspace Email: 21).

Between 2026-06 and 2026-07, Mimecast went from 1.6% to 1.3% of all tracked sites, while Rackspace Email went from 0.88% to 0.85%. Rackspace Email is gaining ground faster in our index.

No. A site runs a single email host, so Mimecast and Rackspace Email are mutually exclusive.

Adoption is counted from Site Stats Database's own crawl; Domain Rating comes from Ahrefs and traffic from DataForSEO. Figures reflect the sites we track and refresh at least monthly.