Email Address Validator
Check email syntax and split out the local and domain parts.
Syntax check only — runs in your browser with no DNS or network lookups.
How to use
- 1 Type or paste an email address.
- 2 See whether the syntax is valid.
- 3 Read the normalized address, local part and domain.
- 4 If invalid, fix the issue named in the message.
About Email Address Validator
The Email Address Validator checks whether an address is syntactically valid and breaks it into its parts.
It applies sensible RFC-5321/5322-inspired rules: there must be exactly one separating “@”, the local part and domain must be non-empty and within length limits, dots cannot be doubled or sit at the edges, and the domain must end in a real top-level domain of at least two letters.
When the address is valid, you get a normalized form — trimmed, with the domain lowercased — alongside the extracted local part and domain so you can use them directly.
When it is not, you get a short, specific reason: a missing “@”, an empty domain, an illegal character, or a missing TLD.
That makes it easy to explain to a user why their input was rejected, or to debug data you are importing.
This is offline syntax validation only.
It deliberately performs no DNS or SMTP lookups, so it never touches the network and cannot prove a mailbox actually exists — it only proves the address is well-formed.
Everything runs in your browser, which keeps the addresses you test private.
Use it to clean a list, validate form input client-side, or sanity-check an address before sending.
FAQ
Does it check whether the mailbox exists?
No. It validates syntax only and never performs DNS or SMTP lookups, so it cannot confirm an inbox is real or deliverable.
Why was a valid-looking address rejected?
Common causes are a missing top-level domain (e.g. user@localhost), consecutive dots, or characters not allowed in an unquoted local part.