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Email Address Checker

Paste a list of email addresses and see which look valid, which are risky and which can't receive mail.

About Email Address Checker

Use the email address checker before a newsletter goes out, after importing leads from a web form, or when free-trial signups look suspicious. Bounces hurt your sender reputation, and many bad addresses are easy to catch. Paste addresses one per line, or separated by commas or spaces, and click Check emails. You can check 20 at a time without an account, 50 with a free account and 500 as VIP. Before a big send, make sure your own domain's SPF record is in order with the SPF Record Checker.

Each address is checked for valid syntax, whether its domain exists and has MX records, whether the domain is one of more than 100 known disposable-mail services, role addresses such as admin@ or support@, free providers, and likely typos with a suggestion, such as gmial.com to gmail.com. You get valid, risky, invalid or unknown with the reasons, and a CSV export. The checker never connects to the recipient's mail server, because that kind of probing gets IP addresses blocklisted, so it can't prove a mailbox exists.

How to use Email Address Checker

  1. 1
    Paste the addresses

    Put one per line, or separate them with commas, spaces or semicolons, and duplicates are removed.

  2. 2
    Click Check emails

    Each domain is looked up once, however many addresses share it.

  3. 3
    Read the verdicts

    Valid, risky, invalid or unknown, each with its reasons and a suggestion for typos.

  4. 4
    Export the clean list

    Filter the table, copy it, or save it as CSV for your mailing tool.

Why use Cubfile for this

  • Domain and MX check

    Finds domains that don't exist, refuse mail with a null MX, or have no mail server.

  • Typo suggestions

    gmial.com points to gmail.com and hotmial.com to hotmail.com.

  • Disposable and role flags

    Throwaway domains are marked risky, and admin@, info@ or support@ addresses are labeled.

  • No SMTP probing

    Recipients' mail servers are never contacted, so the check is quiet and safe.

FAQ

Email Address Checker: questions and answers

Can the email address checker tell if a mailbox really exists?
No. That would mean connecting to the recipient's mail server and pretending to send, which gets IP addresses blocklisted, and many servers accept every address anyway. The checker covers everything short of that, from syntax and domain to mail servers, disposable domains and typos.
What makes an address risky rather than invalid?
Risky means it may work but deserves a look, such as a disposable domain, a likely typo on a domain that has mail servers, or a domain without MX records that falls back to its own address. Invalid means it can't receive mail as written. The MX Record Lookup lists a domain's mail servers in priority order.
Why are role addresses like info@ flagged?
They usually reach a team or a shared inbox rather than one person, and tend to engage less with mailings. The label is only a reason, and the address still counts as valid.
How many addresses can I check at once?
Up to 20 per check without an account, 50 with a free account and 500 as VIP. Checks share an hourly allowance and don't use your daily tasks.
Do you store the addresses I check?
No. The list goes to our server only to run the check and isn't saved, and only the domain part of each address is looked up in public DNS.
Share Email Address Checker with a friendIt runs in any browser, and they can try it without signing up.

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