Question 1

How do I check if an email address is valid for free?

Accepted Answer

Paste or drop a CSV of addresses into the email validator above and press Validate. Every address is checked for RFC-strict syntax, a real IANA-registered TLD, working DNS and MX records, SPF and DMARC records, disposable domains, role accounts and likely typos — free, unlimited and with no API key or signup.

Question 2

What is the difference between an email validator and an email verifier?

Accepted Answer

An email validator checks everything that can be proved without contacting the mailbox: syntax, TLD, DNS/MX, authentication records, disposable and role patterns, provider rules. An email verifier goes one step further and performs an SMTP-level check to confirm the mailbox itself accepts mail. On DebounceNow validation is free and verification uses pay-as-you-go credits.

Question 3

Can I validate a bulk email list or CSV?

Accepted Answer

Yes. Import any CSV — the tool finds the column containing email addresses automatically and de-duplicates them — or paste thousands of addresses separated by commas, spaces or new lines. Results stream in progressively and every address is included in the CSV export, even beyond the rendered preview.

Question 4

Does the email checker tell me who hosts the mailbox?

Accepted Answer

Yes. MX records are classified into the real mailbox provider: Google Workspace, Microsoft 365, Outlook / Hotmail / Live, Yahoo, iCloud, Zoho, Proton, GoDaddy (secureserver.net), Amazon SES and more, along with whether the address is a free mailbox or a business domain.

Question 5

How does it detect disposable and role-based email addresses?

Accepted Answer

Each domain is matched against a bundled list of thousands of disposable and temporary-mail domains, and the local part is matched against role patterns such as info@, sales@, support@, admin@ and noreply@ — the addresses that typically hurt sender reputation and inbox rates.

Question 6

What does a null MX or parked domain result mean?

Accepted Answer

A null MX record (a single "." entry) means the domain has explicitly declared that it accepts no mail, so nothing sent there can ever be delivered. A parked domain resolves but has no working mail host. Both are safe to remove from a list without spending any verification credits.

Question 7

Is my email list stored or shared?

Accepted Answer

No list is stored on a server for you to worry about: validation runs per address through the app's own checks, results stay in your browser session and job history lives in your browser's local storage. You can clear results at any time with the Clear button.

Question 8

How accurate is free email validation?

Accepted Answer

Free validation reliably removes addresses that cannot possibly receive mail — bad syntax, invalid TLDs, missing or null MX, dead domains, disposable providers. It cannot confirm that a specific mailbox exists, which is what SMTP verification adds. Running the free layer first means you only spend credits on addresses that are still plausible.

Question 9

Do I need an API key or account to use the validator?

Accepted Answer

No. The validator is free, unlimited and needs no API key or account. An account is only required if you want to buy credits for SMTP-level verification.

Email validator & mailbox detector

Email validator FAQ