Instantly check whether an email address is valid — correct format, common typos, and whether its domain can receive mail. Free and private, right in your browser.
Enter one or more email addresses (one per line)
Instantly check whether an email address is validly formatted and whether its domain can receive mail. Free — your addresses stay in your browser.
Paste the addresses
Enter one email address, or a whole list, one per line.
Run the check
Each address is validated for correct syntax and common typos.
Check the domain
Optionally confirm the domain has a mail server that can receive email.
Verify for real
Run a full deliverability check before you send to the list.
Sending to malformed or mistyped addresses bounces, and a high bounce rate quietly wrecks your sender reputation — pushing even your good emails into spam.
This free email checker catches the obvious problems first: bad syntax, missing domains, consecutive dots, and the classic typos like gmial.com. It can also confirm the domain actually has a mail server, right from your browser.
A perfectly formatted address can still be dead — the mailbox may not exist, or it may be a catch-all that accepts everything and tells you nothing.
When you need certainty, Emailchaser's free email verifier performs a full deliverability check on each address so you only send to inboxes that are real.
Every address has two parts split by a single @ symbol: the local part (the name before it) and the domain (after it). The local part may contain letters, digits and a defined set of symbols — . ! # $ % & ' * + / = ? ^ _ ` { | } ~ - — but a dot can't start it, end it, or appear twice in a row. The domain has to be a real hostname: letters, digits and hyphens grouped into labels of 1 to 63 characters each, finishing with a dot and a top-level domain such as .com or .io. Those are the exact rules this email checker enforces, so a green result means the address is structurally sound.
The standard behind this (RFC 5321 and 5322) adds a few limits worth knowing. The local part can be at most 64 characters and the whole address at most 254. The spec technically permits quoted, space-containing local parts, but virtually no mail provider accepts them, so the checker treats any space as an error — which is what you want in practice. And a domain with no dot at all, like bob@localhost, only works inside a private network, never for public email.
Most bad addresses aren't structurally broken — they're one keystroke off. The classic is a fat-fingered provider domain: gmial.com, gmai.com, gnail.com and gmaill.com are all just gmail.com with a slip, and hotmial.com, yaho.com, outlok.com and iclould.com follow the same pattern. The checker keeps a list of these and, when it sees one, flags the address and suggests the correct version inline (Did you mean name@gmail.com?), so you can fix it on the spot instead of guessing.
The other frequent culprit is a truncated top-level domain — gmail.co, gmail.con and yahoo.co almost always mean gmail.com or yahoo.com, and the checker catches those too. Copy-paste from a spreadsheet or PDF adds its own noise: a leading space, a stray comma, or two addresses run together with no separator. Because malformed and mistyped addresses are the single biggest cause of hard bounces, cleaning them out before you import a list protects your sender reputation from the very first send.
A syntax check works at two levels, both instant and free. It reads the address to confirm the format is legal, then — with the MX option on — runs a DNS lookup to confirm the domain actually publishes a mail server, the same check our MX lookup performs. What it never does is open a conversation with that mail server, so on its own it can't tell you whether the specific mailbox exists.
Full verification goes the extra step. Emailchaser's email verifier connects to the receiving server and checks the individual mailbox, then layers on the things format alone can't see: catch-all domains that accept every address, disposable and role-based accounts (info@, sales@), and known dead mailboxes. Rule of thumb — use the syntax checker to strip obvious junk out of a list in seconds, then verify the survivors right before a send, when a bounce would actually cost you.
Some addresses look wrong but are perfectly valid, and provider-specific quirks are usually why. Gmail ignores dots in the local part, so jane.doe@gmail.com, ja.ne.doe@gmail.com and janedoe@gmail.com all land in the same inbox. It also supports plus-addressing: anything after a + sign (jane+newsletters@gmail.com) is stripped off and delivered to jane@gmail.com. Both forms pass this checker because both are legitimately formatted — don't mistake them for typos and delete them.
Plus-addressing isn't a Gmail-only trick; Outlook.com and Microsoft 365 accept the same jane+tag@ convention, and plenty of other providers do as well. The practical takeaway: a + sign or an extra dot is a routing feature, not an error. When you de-duplicate a list, normalize Gmail addresses (drop the dots and any +suffix) before comparing them, rather than throwing them out.
How do I check if an email address is valid?
Paste one or more addresses above and the checker instantly confirms whether each is correctly formatted, flags common typos (like gmial.com), and — optionally — checks whether the domain has a mail server that can receive email. For a full deliverability check, verify the address too.
What's the difference between a valid format and a real email?
A valid format just means the address is written correctly (name@domain.com with allowed characters). A real email is one that actually exists and can receive mail. This tool checks the format and whether the domain accepts mail; an email verifier confirms the mailbox itself exists.
Does this checker detect email typos?
Yes. It catches missing @ symbols, spaces, missing domain extensions, consecutive dots and common provider misspellings such as gmial.com, hotmial.com and yaho.com — and suggests the correct address.
Is the email checker free?
Yes — it's free, needs no signup, and the syntax check runs entirely in your browser. The optional mail-server (MX) check uses a public DNS lookup; your addresses are never stored.
Are email addresses case sensitive?
In practice, no. The domain half is always case-insensitive, and although the standard technically allows the local part to be case-sensitive, effectively every major provider — Gmail, Outlook, Yahoo — treats John@ and john@ as the same mailbox. It's safe to store and compare addresses in lowercase, which is why this checker reports the domain in lowercase.
Are dots and plus signs allowed in an email address?
Yes, both are valid characters in the local part. A plus sign enables plus-addressing (you+tag@domain.com), and dots are fine as long as one doesn't start it, end it, or repeat back-to-back. On Gmail specifically, dots are ignored and anything after a + is stripped, so several different-looking addresses can all reach the same inbox.
Why does a correctly formatted email still bounce?
Valid syntax only proves the address is written correctly, not that mail will be accepted. It can still bounce if the mailbox doesn't exist, the inbox is full, the domain has no working mail server, or the receiving server blocks the message. To catch a non-existent mailbox before you send, run the address through a full email verifier rather than a format check.
Can I check more than one email address at once?
Yes. Paste a whole list — one address per line, or separated by commas or semicolons — and the checker validates every one and shows how many have a valid format. With the MX option on, it looks up each unique domain only once, so checking hundreds of addresses across a handful of domains stays fast.
What is the maximum length of an email address?
The standard caps the local part (before the @) at 64 characters and the entire address at 254 characters. Real addresses almost never come close, so hitting either limit is usually a sign of pasted or corrupted data rather than a genuine address.
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