So you think you can validate email addresses A journey down RFC5321

FOSDEM · 27K views · 2018-02-10 · 16:26

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Overview

Stavros Korokithakis gives a FOSDEM 2018 talk on how hard it is to validate email addresses properly, taking a tour through RFC 5321.

On Hacker News

Linked whenever email validation comes up as a fun illustration of how deceptively difficult it is.

Discussed on HN; no positive recommendation is recorded in this export · HN mentions 2019–2025

Topics

Networking & internet infrastructure Software (other)

What people said

stavros · 2025-08 · Reference
This is fun, but it feels suspiciously close to my old presentation about the exact same thing: [VIDEO] Maybe it's just a coincidence, but a shoutout would have been nice if not.
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stavros · 2022-04 · Reference
I gave a very fun talk on the topic in FOSDEM (VOLUME WARNING!): [VIDEO] It's more a joke than edifying, but it was very fun for me (and, I think, the audience), and illustrates the difficulty of email validation well.
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sybercecurity · 2021-03 · Reference
always relevant: "So you think you can validate email addresses": [VIDEO] Which is also why proposals to put email certs (S/MIME, OpenPGP) in the DNS led to hashing the local part, as DNS only allows ASCII and is case insensitive.
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Sources

Video by FOSDEM, played through YouTube.

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