What’s true about email.
Right now.
A dated, cited reference for the rules that govern marketing email. When a regulator or a mailbox provider moves, the page moves, and you get told.
- 14
- rules
- 13
- in force
- 1 Aug 2026
- last verified
Free, no account. We sell no tracking pixels, no seed tests and no open-rate analytics, which is why this can tell you when they are a problem.
Browse
14 rules, seven ways to get bitten
Grouped by the thing that actually goes wrong, not by which regulator wrote it.
Consent and tracking
Permission to email, permission to measure, and why they are not the same thing.
Authentication
SPF, DKIM, DMARC, alignment, and the traps that pass a checker but fail in the wild.
Provider rules
What Gmail, Yahoo, Microsoft and Apple require, with the numbers they enforce on.
Content and claims
What a subject line may promise, and what happens when the promise is not true.
AI disclosure
When AI-generated copy and imagery must be labelled, and when they must not.
Measurement
Which numbers still mean something, and which ones your platform is flattering.
Bounces and hygiene
Suppression, retries, and the classifications every platform gets slightly wrong.
What this is
Three things it is not.
Not a course.
No modules, no certificate, no drip sequence. One page per rule, readable in forty seconds, then you get back to work.
Not a forum.
No login, no invite, no unsearchable Slack history. Every rule is a public URL you can paste to your boss or your lawyer.
Not opinion.
Every claim names its primary source and the date it was last verified. Where the evidence is thin, the page says so.
The check
Does your own sending follow these rules?
Point it at your sending domain. It reads authentication, consent posture and content claims against every rule here, then names what is exposed and the date each rule started to apply.
Free · no account · findings with sources, never a score
Get told when a rule moves
One email per change, and nothing else, ever. Or take the RSS feed instead.