Skip to content
Kordu Tools Kordu Tools

Email Validator

Check if an email address is valid — syntax, MX records, and disposable email detection.

Last updated 08 Apr 2026

Validate any email address in seconds. This tool checks RFC 5322 syntax, verifies the domain has MX records via Cloudflare DNS-over-HTTPS, and flags known disposable or throwaway email providers. Results include a clear pass/fail verdict for each check. Runs entirely in your browser — no email address is stored or shared.
Loading rating…

How to use

  1. 1

    Enter an email address

    Type or paste the email address you want to validate into the input field.

  2. 2

    Click Validate

    Click the Validate button or press Enter to run all checks.

  3. 3

    Review each check

    See a pass, fail, or warning result for syntax, domain format, MX records, and disposable email detection.

  4. 4

    Interpret the verdict

    A green 'Valid' result means the address has correct syntax and the domain can receive email. A red 'Invalid' result means the address cannot receive email. A yellow 'Risky' result means the address uses a known disposable provider.

Frequently asked questions

What does this email validator check?
It checks four things: RFC 5322 email syntax (correct format), domain hostname validity, MX record existence (does the domain have mail servers?), and whether the domain belongs to a known disposable or throwaway email service.
Does this tool send a test email?
No. The validator does not send any email. It checks the address format and DNS records only — no SMTP connection is made, and no email is ever sent.
What is an MX record and why does it matter?
MX (Mail Exchange) records specify which mail servers handle incoming email for a domain. If a domain has no MX records, it cannot receive email — even if the address looks syntactically correct.
What are disposable emails?
Disposable email addresses (also called throwaway emails) are temporary inboxes that expire after a short time. Services like Mailinator, Guerrilla Mail, and Temp Mail provide them for free. They are commonly used to bypass registration requirements or spam filters.
Is a 'Risky' result the same as invalid?
No. A 'Risky' result means the address appears syntactically valid and the domain can receive email, but the domain is a known disposable email provider. The address will likely work now but may expire. Whether to accept it depends on your use case.
Why might a valid email still not receive messages?
This tool checks format and DNS, not the specific mailbox. An address can pass all checks but the mailbox itself may not exist. Full SMTP verification (RCPT TO probe) is not supported — it requires connecting to the mail server, which most servers block.
Is my email address stored or shared?
No. The only external request is a DNS lookup to Cloudflare's DNS-over-HTTPS API to check MX records. Your email address is never sent to any server or stored anywhere.
Can I use this to validate email lists in bulk?
This tool is designed for single-address validation. For bulk validation of large lists, a dedicated email list hygiene service is more appropriate.

Instantly check whether an email address is valid and deliverable.

The validator runs four checks in sequence: RFC 5322 syntax validation,

domain hostname format, MX record verification (does the domain have

mail servers?), and disposable email detection against a curated list

of 100+ known throwaway providers like Mailinator, Guerrilla Mail,

and Temp Mail.

Each check returns a clear pass, fail, or warning status with an

explanation — so you know exactly why an address was rejected. The

tool also identifies free personal email providers (Gmail, Yahoo,

Outlook, etc.) as an informational signal, without penalising them.

Who is this for: developers validating user input, marketers cleaning

email lists, and anyone who needs to check whether an address is real

before sending.

Related tools

MX Lookup

Look up MX records for any domain — mail server priority, IP addresses, and email provider detection.

SPF Record Checker

Look up and validate SPF records — parse mechanisms, detect misconfigurations, and check email authentication.

DNS Lookup

Query all DNS record types for any domain — A, AAAA, MX, TXT, CNAME, NS, SOA, CAA — via Cloudflare DoH.

WHOIS Lookup

Look up domain registration details — registrar, creation/expiry dates, nameservers, and DNSSEC — via RDAP.

Learn more

SPF, DKIM, and DMARC Explained: Stop Emails Going to Spam

How SPF, DKIM, and DMARC work together to stop email spoofing and spam folders. Google now rejects 75% of unauthenticated email from bulk senders.

DNS Record Types Explained: A, AAAA, CNAME, MX, TXT

Every DNS record type explained with real dig examples. Covers A, AAAA, CNAME, MX, TXT, NS, SOA, PTR, SRV, and CAA records used across 350M+ domains.