Comparisons

Compare SPF mechanisms, policies, and related email authentication technologies.

Should you use hard fail or soft fail? Include or redirect? SPF, DKIM, or both? These side-by-side comparisons break down the differences between SPF mechanisms, enforcement policies, and email authentication protocols so you can make the right choice for your setup.

SPF a vs mx Mechanisms: When to Use Each

The SPF a and mx mechanisms both authorize servers by hostname, but they resolve differently. Learn when to use each — and when ip4 is the better choice.

SPF Creator vs AutoSPF: SPF Flattening Comparison

Comparing SPF Creator and AutoSPF for managing SPF records. One helps you build records that stay under the lookup limit, the other flattens records that exceed it.

SPF Creator vs MXToolbox: SPF Generator Comparison

Comparing SPF Creator and MXToolbox for generating SPF records. See how the dedicated SPF generator stacks up against the popular email diagnostics suite.

SPF Hard Fail vs Soft Fail: -all vs ~all

Should your SPF record end with -all or ~all? Learn the difference between hard fail and soft fail, how receivers handle each, and which to use.

SPF include vs redirect: When to Use Each

SPF include and redirect both reference other domains' SPF records, but they work differently. Learn when to use each and avoid common mistakes.

SPF vs DKIM vs DMARC: Email Authentication Compared

A clear comparison of SPF, DKIM, and DMARC — what each does, how they work together, and which to implement first.

SPF vs DKIM: What's the Difference?

SPF and DKIM both authenticate email, but they work differently. Learn what each protects against, how they handle forwarding, and why you need both.