Specification
Everything a good email does
Requirements are grouped by the part of the email system they affect. Each topic is testable and links to its source standard.
3 topics
Foundations
Message format, headers, MIME, identity, and the envelope.
3 topicsAuthentication
SPF, DKIM, DMARC, transport security, and domain trust.
3 topicsDeliverability
Reputation, list quality, bounces, and inbox placement.
3 topicsAccessibility
Readable, operable messages for people of all abilities.
3 topicsRendering
HTML and CSS that survive real-world email clients.
3 topicsPrivacy
Consent, tracking, data minimisation, and respectful measurement.
3 topicsInternationalisation
Unicode, language, direction, and international addresses.
3 topicsLifecycle
Subscription, unsubscribe, complaints, retries, and expiry.
3 topicsSecurity
Injection, dangerous content, phishing resistance, and secrets.
3 topicsAutomation
Machine-readable actions, calendars, receipts, and agent use.