Email validator: check an email address free and privately
To validate an email address free, type or paste it into the Email address box and press Validate. The tool checks that the address is written correctly under RFC 5321 and RFC 5322, then looks up whether its domain publishes a mail server. You get one of four answers: Looks deliverable, Disposable inbox, Not deliverable or Not checked.
An email validator is a tool that tests whether an address is well-formed and whether its domain can receive mail. This one is not fully offline, and it says so: the format, role, free-provider, disposable and typo checks run in your browser, and only the domain is sent for the mail-server lookup. The name before the @ stays on your device.
A positive result means the address is well-formed and its domain accepts mail, not that a person reads the mailbox. To see the records behind a result, use the DNS lookup tool; to see who registered the domain, the WHOIS lookup.
Table of Use: what you enter and what comes back
| You enter | The tool shows | What to do |
|---|---|---|
| A well-formed address at a domain with MX records | Looks deliverable, with the MX hosts in priority order | The domain can receive mail; send a message to confirm the person |
| A typo such as gmial.com or hotmail.con | A “Did you mean” button with the corrected address | Click it; the corrected address is checked at once |
| Text with no @ sign, a space or two dots in a row | Not deliverable, naming the broken rule | Fix the text; nothing is sent while the format is invalid |
| An address at a throwaway-inbox service such as Mailinator | Disposable inbox | Ask for a permanent address or drop it |
| A domain with no mail server, or a null MX record | Not deliverable, with the cause (RFC 7505 for null MX) | Look for a typo or an expired domain |
| A shared mailbox such as info, sales or support | Looks deliverable with a Role-based tag | Fine for business contact; often kept out of newsletters |
| Up to 1,000 addresses in Bulk Validation | One row per address, copy buttons and a CSV export | Keep deliverable, review disposable, drop undeliverable, retry Not checked |
The export opens in a spreadsheet, or becomes script-ready data through the CSV to JSON converter. To pull addresses out of a block of text first, a regex tester helps.
Features of this email address checker
- Format check. One @ sign, no spaces or doubled dots, at most 64 characters before the @ and 254 in all, and a top-level domain of letters. Invisible characters from copy-pasting are caught. Quoted and non-Latin local parts pass with a warning; non-Latin domains are looked up in punycode form.
- MX lookup. Mail servers are listed in priority order. With no MX record, an A record counts as an implicit mail host under RFC 5321; a null MX record marks the domain not deliverable.
- Disposable, role and free-provider flags. Built-in lists of more than 50 throwaway-inbox domains, shared mailbox names such as info and noreply, and consumer providers such as Gmail. The lists are finite, so a clean result does not prove an address is permanent.
- Typo suggestions. A domain one edit away from gmail.com, yahoo.com, hotmail.com, outlook.com or five other popular domains, or one of those names with a broken ending, gets a one-click fix.
- Bulk validation. Up to 1,000 addresses and 25 different domains per batch, split on new lines, commas and semicolons, de-duplicated case-insensitively. Export CSV saves email_validation_results.csv with the result, MX hosts, the disposable, role-address and free-provider flags, any Did you mean suggestion and the explanation. A name-plus-angle-bracket entry or a mailto: link is reduced to the bare address.
Exactly what leaves your device
Malformed addresses are decided in the browser and send nothing. For a well-formed address the page makes one request per distinct domain to ZipConvert's own /api/email-validate address, carrying the domain and the placeholder mailbox name postmaster. ZipConvert's lookup function then asks Cloudflare's DNS-over-HTTPS resolver for the MX records, and for the A record when there are none. It does not save the domain or the result; it keeps only a per-IP request counter that expires after about two minutes, to enforce a limit of 30 lookups a minute.
What it does not check
There is no SMTP mailbox probe, so no mail server is ever asked whether an inbox exists. SPF, DKIM and DMARC are not checked, and catch-all domains are not detected.
How to validate an email address, step by step
- Leave Single Email selected for one address, or choose Bulk Validation for a list.
- Type or paste the address into the Email address box.
- Press Validate or the Enter key. The button reads Checking… while the domain is looked up.
- Read the result badge and the sentence under it, then the Validation Checks, Email Type and MX Records cards.
- If a Did you mean button appears, click it to check the corrected address.
- For a list, paste one address per line and press Validate All. Take each result group with the Copy buttons or use Export CSV, and re-run Not checked after a minute.
Phone numbers in the same list can be tidied with the phone number formatter. The same format-first approach drives the credit card validator and the IBAN validator.
Who can use it
- Marketers and newsletter owners cleaning an export before a send to cut bounces.
- Developers testing what a sign-up form should accept, including quoted, plus-tagged and internationalised addresses. The email template builder covers the message once the list is clean.
- Support and sales teams checking that a customer typed an address correctly before a quote goes out.
- Anyone wary of a sender who wants to know whether the domain publishes mail servers. Once you have a mail host's IP address, the IP address lookup shows where it is.
FAQs
How do I check if an email address is valid for free?
Type or paste the address into the Email address box on this page and press Validate. The tool first checks the format against RFC 5321 and RFC 5322 rules in your browser, then looks up the mail servers of the domain. A green "Looks deliverable" result means the address is well-formed and its domain accepts mail. It does not confirm that the individual mailbox exists.
Is it safe to enter an email address into an email validator?
With ZipConvert's email validator, only the domain leaves your device. The format, role, free-provider, disposable and typo checks run in your browser. For the mail-server check, the page asks ZipConvert's lookup function about the domain, using the stand-in mailbox name postmaster, and that function queries Cloudflare's DNS-over-HTTPS resolver. The name you typed before the @ is never sent, and an address that fails the format check sends nothing. The Network tab in DevTools shows the request.
Can an email validator tell whether a mailbox really exists?
Not reliably, and this one does not pretend to. There is no SMTP mailbox probe. Many large providers accept every address during the SMTP conversation and bounce later, so a probe says little, and probing other people's mail servers to enumerate addresses is what list scrapers do. The only dependable proof is sending a message, which is what double opt-in confirmation is for.
How do I validate a list of email addresses in bulk?
Switch to Bulk Validation and paste up to 1,000 addresses, one per line or separated by commas or semicolons. Entries written as a name followed by an address in angle brackets are understood, and duplicates are removed. Each distinct domain is looked up once, up to 25 different domains per batch. Press Validate All, copy each result group, or click Export CSV to download a spreadsheet-ready file.
What do Looks deliverable, Disposable inbox, Not deliverable and Not checked mean?
Looks deliverable: the format is valid and the domain has a mail server, either an MX record or an A record that RFC 5321 treats as an implicit mail host. Disposable inbox: the domain accepts mail but belongs to a known throwaway-inbox service. Not deliverable: the address is malformed, the domain has no mail server, or it publishes a null MX record. Not checked: the lookup failed or was skipped, so no judgement was made.
What is the difference between email syntax validation and email verification?
Syntax validation checks that the text follows the rules for an address, such as one @ sign, allowed characters and length limits. Verification tries to confirm that the mailbox exists, usually by an SMTP probe or by sending a message. This tool does the syntax check plus a domain-level mail-server check, which sits in between. It does not probe mailboxes, and it does not check SPF, DKIM, DMARC or catch-all domains.