Free Tool
Free Email Existence Checker
An email existence checker tells you whether an email address actually exists and is valid, without sending a message to it. We check the address syntax, look up the domain, and run an SMTP probe to confirm the mailbox accepts mail. 10 checks per day, no signup, no card.
Need to check existence on every signup or clean a list? Use the API
Paste an address above. Or try one of the examples below.
What is an email existence check?
An email existence check confirms whether a specific mailbox is real before you rely on it. It is different from a syntax check, which only confirms the address is formatted correctly. To verify an existing email address, we resolve the domain's mail servers and open an SMTP handshake with the destination server, then read how it responds to the address. The server tells us whether the mailbox accepts mail, all without sending anything. A valid result means the address exists and can receive mail. An invalid result means the server rejected it, so the mailbox does not exist.
How do I check if an email address is valid?
To check an email address validity, enter it above. The email validity checker returns whether the address is valid, whether the domain is set up to receive mail, and an honest deliverability status. The same check works for any email id, on any domain, including Gmail, Outlook, and custom company domains.
Valid, invalid, risky, or unknown
The headline result. Valid means the mailbox exists and accepts mail. Invalid means the server rejected the address, so it does not exist. Risky and unknown mean the answer could not be confirmed, and we tell you why instead of guessing.
Domain and MX record validity
We resolve the domain's MX records to confirm it can receive mail at all. A domain with no MX records cannot accept email, so the address is invalid no matter how it is spelled. This is the email domain validity check, separate from the specific mailbox.
Honest deliverability status
Alongside the verdict you get the status the API returns: safe, risky, invalid, or unknown. We never label a guess as valid. If the mailbox cannot be confirmed, the status says so, so you can decide how much to trust the address.
How do you verify an email address without sending an email?
Verifying an email address without sending email is an SMTP behavior test, not a guess. We ask the destination mail server whether it will accept the address, and stop before any message is sent. The recipient sees nothing.
Resolve the MX records
First we look up the domain's MX records to find its mail servers. No MX records means the domain cannot receive mail, so the address is invalid before we go further. Working MX records are the prerequisite for the next step.
Open an SMTP handshake
We open a connection to the mail server and run the handshake up to the point where the server decides to accept or reject the address. We stop there. No message is queued, sent, or delivered, so the mailbox owner is never notified.
Read the server's answer
The server's response tells us whether the mailbox exists. An acceptance maps to valid, a rejection maps to invalid. When the server accepts every address or blocks the probe, we cannot confirm the mailbox, so we return risky or unknown rather than a false valid.
Why does email existence matter?
A made-up or dead email address costs you every time it slips through. Checking existence up front is how you keep fake signups, bounces, and dead leads out of your system.
Catch fake and made-up signups
People type fake addresses into signup forms to skip verification or abuse a free tier. An existence check tells you if the address is real before you create the account. Pair it with disposable detection to catch throwaway addresses too.
Stop bounces before you send
Every message to a dead address bounces, and a high bounce rate lowers your sender reputation with Gmail, Outlook, and Yahoo. Confirming the mailbox exists before you send keeps your bounce rate down and your mail in the inbox.
Know if a lead is legit
A form fill is only worth chasing if the address is real. Checking whether an email is legit before it reaches sales means no one wastes time on an address that never existed.
An honest verdict, never a false valid
Some addresses cannot be confirmed, and we say so. We would rather flag an address risky or unknown than label a guess valid. An honest risk flag is more useful than a confident wrong answer.
Why is a catch-all or probe-blocked address flagged risky or unknown?
Existence checking has honest limits, and we surface them instead of hiding them. Two cases cannot return a clean valid.
A catch-all domain accepts mail for every possible address, real or not. The mailbox you entered and a random string both get accepted, so the SMTP response proves nothing about the specific mailbox. We flag these addresses risky: deliverable at the server, unconfirmed at the mailbox. For a domain-level look at this, use the catch-all email checker.
Some servers, including large providers, block verification probes or give no clear answer. When that happens we return unknown rather than guess. A Gmail validity check, for example, can confirm the domain and MX records, but Gmail limits how much the SMTP layer will reveal about an individual mailbox. We report what we can prove and label the rest honestly. For the full multi-signal check, use the email verifier.
What does email existence detection cost at scale?
This tool is free for 10 checks a day, no signup. To check existence on every signup or across a list, the same check ships in the email verification API. 100 validations a month free, no card required, then $49.99 a month for 50,000.
Pay for what you check. Cancel anytime. Overage is billed through Stripe at $0.001 per validation regardless of volume.
What counts as a validation? One request to the validation endpoint is one validation. Failed calls (4xx from your side) do not count.
Frequently asked questions
How do I check if an email address exists?
Enter the address in the checker above and we run the check in real time. We resolve the domain's MX records and open an SMTP handshake with the destination mail server to see whether it accepts mail for that mailbox. A valid result means the address exists. An invalid result means the server rejected it. No message is ever sent.
Can you verify an email address without sending an email?
Yes. That is exactly what this tool does. It checks the address syntax, looks up the MX records, and opens an SMTP handshake with the mail server without ever sending a message. The server's response tells us whether the mailbox accepts mail. The recipient is never notified.
How do I check if an email is valid?
Paste the address and read the verdict. The checker confirms the syntax is correct, the domain can receive mail, and the mailbox accepts mail, then returns a status of safe, risky, invalid, or unknown. Valid means the address exists and can receive mail. Invalid means it cannot.
Is this email existence checker free?
Yes. 10 checks per day, no signup, no card, no email required. The check is ReCaptcha protected. If you need more, a free Trueguard account lifts you to 100 validations a month through the API, and the paid plan covers 50,000.
Why does the checker flag some addresses risky or unknown instead of valid?
Because we will not label a guess as valid. A catch-all domain accepts every address, so the SMTP response cannot confirm one specific mailbox, and we flag it risky. Some servers block verification probes or give no clear answer, and we return unknown. Both are honest answers, not failures.
Can you check if a Gmail or Outlook address is real?
You can check any provider, including Gmail, Outlook, Yahoo, iCloud, and custom domains. We confirm the domain and its mail servers for all of them. Large providers limit how much the SMTP layer reveals about an individual mailbox, so some results come back risky or unknown rather than a hard valid.
How is email existence different from email deliverability?
Existence is whether the mailbox is real and accepts mail. Deliverability is whether your message actually lands in the inbox, which also depends on your sender reputation, content, and the recipient's filters. This tool confirms existence. It cannot promise a message will reach the inbox after delivery.
Is there an API to check email existence at scale?
Yes. The same check runs in the Trueguard email verification API at POST /email/validation. It returns the existence verdict and deliverability status as structured fields you can act on in your backend. 100 free validations a month, then $49.99 a month for 50,000.
