Email validator

Client

Format check and typo hints—local only.

Syntax validation is not mailbox verification

This page checks the shape of an email address and highlights common domain typos. Passing syntax does not run SMTP, confirm DNS delivery, prove that the mailbox exists, or show that its owner can receive a message.

Use confirmation email or another consent-based verification flow when your application must establish mailbox control. Avoid SMTP probing, which can be unreliable and intrusive.

Normalize lists without changing identity

Trim accidental surrounding whitespace and review typo hints, but do not assume the local part is case-insensitive or remove dots and plus tags across every provider.

For a pasted list, use Extract emails before Email normalizer so extraction, validation, normalization, and deduplication remain separate reviewable steps.

Loading…

Nearby workflows on Toolcore

  • Extract emails — to pull candidate addresses from prose or pasted records before checking them.
  • Email normalizer — to trim, lowercase domains, and optionally deduplicate a reviewed list.
  • Regex tester — to test application-specific input patterns without claiming mailbox existence.

Common use cases

  • Catch malformed addresses and obvious domain typos before importing a contact list.
  • Check a user-entered address locally before showing a confirmation-email step.
  • Separate syntax review from list normalization, deduplication, and delivery verification.

Common mistakes to avoid

  • Assuming valid syntax means the mailbox exists

    A format check does not perform SMTP, confirm DNS delivery, or prove that anyone controls the address.

  • Rewriting the local part for every provider

    Dot removal, plus-tag stripping, and case rules are provider-specific and can change the intended address.

  • Using an overly narrow form rule

    Real addresses can contain characters or domain forms that simplistic patterns reject. Use the validator as an input hint, not a complete identity policy.

FAQ

Does this validator check whether a mailbox exists?

No. It checks syntax and offers typo hints only; it does not run SMTP or verify mailbox ownership.

How should an application verify an email address?

Send a time-limited confirmation link or code and require the recipient to complete that consent-based flow.

Should I lowercase the whole address?

Lowercasing the domain is generally safe, but the local part can be provider-dependent. Preserve it unless your own system has a documented normalization rule.

Common search terms

Phrases people search for that match this tool. See the full long-tail keyword index.

  • email syntax validator online
  • check email address format
  • email typo checker no smtp
  • validate email locally in browser

More tools

Related utilities you can open in another tab—mostly client-side.