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Email Address Syntax Validator

Bulk-validates email syntax. Doesn't check deliverability (that requires SMTP probes); flags syntactically broken addresses that would bounce immediately.

Validation results
1 valid3 invalid
john@example.com
invalid-email
user@
@domain.com
What it does

Splits input on newlines, runs each through RFC 5322-compliant syntax check, returns the list with valid/invalid status and reason for invalid.

When to use

Before importing a list into your sending tool. Quick triage on a list of scraped or manually-collected addresses.

FAQ

Does this verify the address actually exists?+

No. Syntax validation only — checks the format is valid. To verify the address exists on a real mail server, use a deliverability-check service (NeverBounce, ZeroBounce, Hunter.io).

You validated the setup. Want the live monitor that watches it forever?

One-time validation catches today's misconfiguration. Outsolvi watches every send forever and flags the day your record stops passing, the day a sender goes rogue, or the day a bounce pattern shifts. From $7/user/mo yearly.

Switch on continuous monitoring
Nate SummersCo-Founder, Outsolvi

Nate built Outsolvi after watching every email-tracking tool he had ever used lie to him about opens. Outsolvi runs Tier 1 to 5 confidence scoring on every open, native in Outlook and Gmail, so the number on the dashboard is one a rep can actually act on.

Last reviewed May 25, 2026Editorially independent

We update these pages when the underlying mechanics change — new mailbox-provider rules, new tracker behavior, new measurement gaps. The dates above are real revisions, not auto-touches.