When you verify an email, Tomba runs several checks and lists them under Show details. This article explains each check in plain words: what it looks at, and what a yes or a no means for you.
The status at the top of the result, such as Valid or Accept All, is the overall answer. The checks show how Tomba got there.
Where to find the checks
Step 1. Open Verify, type an address and click Verify.
Step 2. Click Show details under the result. The link then reads Hide details.
The checks sit in four cards: Format Validation, Domain Type, Server Status and Deliverability. Each card shows a verdict at the top right, then one row per check. When Tomba has the data, two more cards follow: MX Records and Whois Info.
You get the same details when you click the shield icon next to an email in Domain Search or in a finder result. The result opens in a Verify Email window.
What does the message under the status mean?
The line under the status sums up the result:
"This email address can be used safely." means the status is Valid, so you can send.
"The domain example.com accepts all email addresses." means the status is Accept All, with the address's own domain in place of example.com. Tomba can't confirm the mailbox, so send with care.
"This email address couldn't be verified." means the status is Blocked: the mail server refused the check. Send with care, or verify again later.
"This email address isn't used to receive emails." means the status is Invalid. Remove the address from your list.
The Deliverability card repeats the answer. It says "Email can receive messages successfully." for a valid address, and "Email address cannot receive messages." for an invalid one.
Regex: is the address written correctly?
Regex checks the address against the pattern every email address must follow. A space or a missing @ makes it fail. The row is in the Format Validation card.
Pass: the address is written correctly.
Fail: the address is badly written, so it can't receive mail. Look for a typo, fix it and verify again.
When Regex fails, the card usually says "Email format is invalid."
Gibberish: does the address look random?
Gibberish checks whether the part before the @ looks like a run of random letters. The row is in the Format Validation card.
No: the address doesn't look random.
Yes: the address looks made up. Real people rarely use addresses like that, so treat it with care.
When Gibberish says Yes, the card's verdict reads Gibberish instead of Valid, and the card says "Email contains gibberish characters."
Webmail: is it a free email service?
Webmail checks whether the address is on a free email service that anyone can sign up for, such as Gmail, Yahoo or Outlook. The row is in the Domain Type card.
No: the address isn't on a free email service.
Yes: it's a personal webmail address, not a work address. Tomba still checks it and marks it as webmail.
For a webmail address, the card says "This is a webmail service (Gmail, Yahoo, etc.)"
Disposable: is it a throwaway inbox?
Disposable checks whether the address is on a throwaway mail service, the kind people use for a short time and then drop. The row is in the Domain Type card.
No: it isn't a throwaway address.
Yes: it's a throwaway inbox. Tomba doesn't check these, so treat the address as not deliverable. The card says "This is a temporary/disposable email service."
When Webmail and Disposable both say No, the Domain Type card reads Professional and says "This appears to be a professional domain." The address is on a company's own domain, like a work address.
MX Records: does the domain have a mail server?
MX Records are the settings that tell other mail servers where to deliver email for a domain. The domain is the part of the address after the @. The row is in the Server Status card.
Valid: the domain has a mail server set up. The card says "MX records found and SMTP server is accessible."
Invalid: Tomba found no mail server for the domain, so it isn't set up to receive mail. Check the domain for a typo. The card says "No valid MX records or SMTP server issues detected."
When Tomba finds mail servers, a separate MX Records card lists them by name and says how many it found.
SMTP Server and SMTP Check: what do they show?
SMTP is the system mail servers use to pass email to each other. The SMTP Server and SMTP Check rows are in the Server Status card.
SMTP Server shows Online when the domain has a mail server set up, and Offline when it doesn't.
SMTP Check shows Pass when the domain has a mail server set up, and Fail when it doesn't.
⚠️ Important: SMTP Server and SMTP Check don't tell you whether the mailbox exists. The status at the top of the result does.
Accept All: does the server accept every address?
Accept All checks whether the company's mail server accepts mail sent to any address at the domain, even made-up ones. This is called a catch-all domain. The row is in the Deliverability card.
No: the server doesn't accept every address.
Yes: the domain is catch-all. The server says yes to everything, so its yes can't prove that this one mailbox exists.
When the status at the top says Accept All, Tomba can't confirm the mailbox, and the card says "Domain accepts all emails (catch-all enabled)." Send with care. To learn more, see What does Accept All mean?
Blocked: did the server refuse the check?
Blocked shows whether the company's mail server refused to answer Tomba's check. The row is in the Deliverability card.
No: the server didn't refuse the check.
Yes: the server refused the check.
When the status at the top says Blocked, Tomba couldn't confirm the mailbox, and the card says "Verification was blocked by the server." Send with care, or verify the address again later. When you verify one address, a blocked result doesn't use a verification credit.
Greylisted: did the server ask Tomba to wait?
Greylisted shows whether the mail server put Tomba's check on hold and asked it to try again later. Some mail servers do this with senders they don't know yet, to slow down spam. The row is in the Deliverability card.
No: the server didn't hold the check back.
Yes: the server delayed the check.
Whatever Greylisted says, go by the status at the top of the result. It's the overall answer.
SMTP Provider: who runs the company's email?
The SMTP Provider badge next to the score, such as Google Workspace, names the company that runs email for the domain. Hold your pointer over it to see SMTP Provider and the name. Tomba works it out from the domain's mail servers.
The badge shows only when Tomba knows the provider. It's hidden on narrow screens, such as a phone.
Whois Info: who registered the domain?
The Whois Info card shows public details about the domain: the Registrar, the company the domain was registered with, and when it was Created. Click View Whois to open the registrar's own Whois page. These details describe the domain, not the mailbox.
💳 Credits: Verifying an email uses 1 verification credit, and that includes accept-all and invalid results. When you verify one address, disposable and unknown results, including blocked checks, are free. Opening Show details costs nothing. The Free plan has no verification credits.
Common questions
What does "This email address couldn't be verified" mean?
The mail server refused Tomba's check, so the status is Blocked, and Tomba can't say whether the mailbox exists. Send with care, or verify the email address again later. When you verify one address, a blocked result doesn't use a verification credit.
Why does a check say Yes when the status is Valid?
Go by the status at the top of the result. It's the overall answer, and a row such as Blocked or Accept All can still say Yes next to a Valid status.
Does Show details use credits?
No. Show details only opens the checks Tomba already ran when you verified the address.
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