Email checker
Check if an email address is valid before you send to it or let it sign up. We check the format and the domain’s mail servers, ask the server whether the mailbox exists, and flag throwaway addresses.
20 free lookups a day, no account needed. No email is sent: we stop the conversation with the mail server before any message.
Valid: the mailbox exists
- Syntax
- Valid
- Domain
- example-mail.com
- Mail servers
- mx1.example-mail.com
- Mailbox
- Exists
- Accepts any address
- No
- Disposable
- No
- Role address
- No
- Free provider
- No
Example result with a made-up address.
What an email check tells you
A typo or a fake address costs you a bounce, a lost customer, or a sign-up that never was. Most of that shows up before you send anything.
- Whether it can receive mail
- The address is checked for typos, the domain must exist, and it needs mail servers (MX records) to receive anything.
- Whether the mailbox exists
- We ask the receiving mail server if it would accept mail for the address, then hang up without sending. Some servers accept every address; we tell you when that’s the case.
- Whether it’s worth trusting
- Disposable inboxes are made to be thrown away after one sign-up. Role addresses like info@ reach a team, not a person.
Need more than 20 a day?
Validate addresses as people sign up, or clean a list before a campaign. On the TrustLookup API an email check costs 1 credit, and a CSV upload checks a whole list. The email DNS check (SPF and DMARC records) is free.
Request
curl https://api.trustlookup.io/v1/lookup \
-H "Authorization: Bearer $TRUSTLOOKUP_KEY" \
--data-urlencode q="[email protected]" \
-d checks="email"Response (shortened)
{
"type": "email",
"results": {
"email": {
"ok": true,
"credits": 1,
"data": {
"syntax_valid": true,
"has_mx": true,
"disposable": false,
"role": false,
"smtp": {
"checked": true,
"deliverable": true,
"catch_all": false
}
}
}
}
}Questions
Is this email checker free?
Yes. This page checks 20 addresses a day without an account. On the API, an email check costs 1 credit, and the free plan includes 250 credits a month.
Do you send an email to the address?
No. We connect to the domain’s mail server and ask whether it would accept mail for the address, then close the connection before any message is sent. The person never sees anything.
Why does it say the mailbox couldn’t be confirmed?
Some mail servers refuse to say whether a mailbox exists, ask senders to try again later, or block checks from servers they don’t know. The address may still be fine: the format and mail servers are checked either way.
What is a catch-all domain?
A domain set up to accept mail for any address, real or not. Mail won’t bounce at first, but nobody may read it. We can’t confirm a single mailbox on these domains.
What counts as a disposable email?
An address from a throwaway inbox service, made to receive one confirmation link and then be abandoned. We check against a list of more than 100,000 throwaway domains.
Do you keep the addresses I check?
We keep the answer for up to a day so a repeat check is instant, then delete it. It isn’t linked to you, and we never sell or share what you check.
Run these checks from your app
250 free credits every month for phone, email, IP and domain checks. NPI, USDOT and blacklist checks don’t use credits.