Email Glossary

Sender Score

Sender Score is a reputation metric (0-100 scale) originally developed by Return Path (now Validity) that rates the trustworthiness of an email sending IP address. The score is based on complaint rates, unknown user rates, spam trap hits, and sending volume. Scores above 80 are considered good, below 70 indicates reputation problems.

Beyond Sender Score

While Sender Score is a useful reference, major mailbox providers (Gmail, Outlook, Yahoo) maintain their own internal reputation systems that are more sophisticated and specific to their networks. Your Sender Score is an approximation, not the exact score providers use.

Focus on the underlying metrics that drive reputation:

  • Keep complaint rates below 0.1%
  • Maintain bounce rates below 2%
  • Avoid spam traps through list hygiene
  • Authenticate all sending domains

Related Terms

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