Keeps your address
alice@example.com stays alice@example.com. IDMX changes how mail travels between domains, not who
you are.
Mail between domains, over HTTPS
IDMX is an experimental open standard for server-to-server email delivery. Same addresses, same message format, SMTP as the fallback, and authenticated sender domains from day one.
Works with SMTP
When the recipient’s domain does not speak IDMX, the sender uses SMTP as it does today. There is no migration date, and no one has to upgrade first.
Authenticated by default
Every delivery is signed by the sending domain with an HTTP Message Signature (RFC 9421). Keys live in DNS, as DKIM keys do.
Built from standard parts
HTTPS, TLS 1.3, DNS SVCB records, JSON and an OpenAPI contract. No new wire protocol, so you can implement it in any language.
IDMX is experimental. Its first specification draft, v1-draft-00, is in public review. See Status & roadmap.