Level: Intermediate
DMARC alignment can be configured as strict or relaxed for both SPF and DKIM independently, and understanding the difference affects how forgiving your policy is toward legitimate but imperfectly matched mail.
Relaxed Alignment Allows Subdomain Matching
Under relaxed alignment, a message signed by mail.yourcompany.com can align with a From address at yourcompany.com, since it's treated as the same organizational domain.
Strict Alignment Requires an Exact Domain Match
Strict alignment requires the authenticated domain to match the From domain exactly, with no subdomain flexibility, which is more secure but also more prone to unexpected failures.
Most Senders Start With Relaxed Alignment
Relaxed alignment is the more forgiving, commonly recommended default for most sending setups, with strict alignment reserved for organizations with very tightly controlled sending infrastructure.
Next step: Use the Find DNS Records to check whether your current DMARC alignment mode is set to relaxed or strict, and confirm it matches your actual sending setup.