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List of Valid and Invalid Email Addresses

Answer from KonstantinK on Stack Overflow
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GitHub
gist.github.com โ€บ cjaoude โ€บ fd9910626629b53c4d25
Test list of Valid and Invalid Email addresses ยท GitHub
Test list of Valid and Invalid Email addresses. GitHub Gist: instantly share code, notes, and snippets.
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Email Hippo
tools.emailhippo.com
Free Email Address Verifier: Verify An Email Address In Real Time | emailhippo.com
Email Hippo's free online email verification tool. Check if email addresses are valid. Verify email addresses and then download results as PDF, CSV. Try for FREE now.
People also ask

How can I verify an email address?
There are several ways to verify email addresses. If you only have a few addresses to check, verify each one individually through an online email checker. If you check a large number of email addresses each month or have a large batch to verify, use an email verification tool to automate the process.
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clean.email
clean.email โ€บ verifier โ€บ how-to-verify-email-list
How To Verify Email List For Your Cold Email Campaign
How frequently should I verify email lists?
It depends on how large your list is, how often you send a campaign, and your bounce rate. Itโ€™s a good idea to verify email lists of addresses regularly and at least every six months. The smaller the list and the lower the bounce rate, the less often you can clean your list. If your organization adds hundreds of addresses each month, monthly cleaning might be a better idea.
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clean.email
clean.email โ€บ verifier โ€บ how-to-verify-email-list
How To Verify Email List For Your Cold Email Campaign
How to find email addresses with the Email Finder?

To find an email address with Voila Norbert Email Finder, you need two things:

  • The full name of your prospect
  • The domain name (website URL) which your prospect's company uses to send emails from.

Enter this information into Norbert Email Finder and Norbert will spit back a valid email address in less than a second.

Note: If Norbert can't find an email address, double-check that you have the right domain. Some companies use different domain names for their websites and their emails.

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voilanorbert.com
voilanorbert.com
Email Finder: Free 50 Verified Email Addresses - VoilaNorbert
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Voila Norbert
voilanorbert.com
Email Finder: Free 50 Verified Email Addresses - VoilaNorbert
There are many ways how to find someone's email address online... You could check their about page, dig through their social media accounts, or even make a blind guess. But since these manual methods are slow and unpredictable, you can instead use a dedicated Email Finder Tool like Voila Norbert. With Norbert, all you need is your prospect's name and the company URL they're working for. Norbert will then fetch you a valid email address in a breeze.
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Verifalia
verifalia.com โ€บ validate-email
Free email address validator
To initiate the email verification, upload your chosen mailing list to our dashboard in one of the supported formats (CSV, Excel, or plain text); once our email verifier finishes the mail list cleaning process, selectively download deliverable emails, focus on invalid or risky ones, or pick items based on their classifications and statuses among the 40+ supported by Verifalia. Our email validator can identify the most elusive disposable email address providers, such as EmailOnDeck, and can check even the most challenging mail exchangers, including Yahoo!
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Usebouncer
usebouncer.com โ€บ home โ€บ blog โ€บ how to create a valid email address list
How to Create a Valid Email Address List - Usebouncer
June 18, 2025 - This includes providing recipients with clear opt-out mechanisms and respecting their preferences. A valid email list helps reduce bounce rates, which occur when emails are undeliverable.
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Gigasheet
gigasheet.com โ€บ post โ€บ valid-email-address-list
The Easy Way to Build a Valid Email Address List
Valid Email addresses have a pretty specific format and there isn't really any wiggle room: ... And there can't be any spaces in between! For example, in the address [email protected] "info" is the prefix and "gigasheet.com" is the email domain. When email lists with wrong addresses, burner emails, and fake domains are common, you must perform email validation before hitting send.
Find elsewhere
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Kickbox
kickbox.com โ€บ email-list-verification
Check Email Lists to Find Valid Email Addresses with our Drag and Drop Email List Verifier | Kickbox
Connect the Kickbox API to protect your email database from typos & invalid addressesโ€”anywhere you capture email data online. For most businesses (and marketers!) your email list is your most valuable asset.
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Clean Email
clean.email โ€บ verifier โ€บ how-to-verify-email-list
How To Verify Email List For Your Cold Email Campaign
Learning how to verify email address lists is as easy as learning the art of collecting them when you break down the process into individual steps: All mail addresses share the same format: username, followed by the @ symbol, followed by the domain.
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Campaign Refinery
campaignrefinery.com โ€บ valid-email-address-list
5 Ways to Build a Valid Email Address List
December 20, 2024 - How do you add valid email address to your email list? The answer lies in using the double-opt-in method, verifying recipients, and maintaining regular hygiene. The most important of the three is list-cleaning. At Campaign Refinery, our clients get access to an automated list-cleaning feature that detects invalid email addresses and removes them.
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Mailmeteor
mailmeteor.com โ€บ email-checker
Email Checker: Verify email address for free - Mailmeteor
Import your email addresses in Google Sheets and verify them all in one-click. Install the extension and enjoy 50 email verifications per month for free. ... Give it a try with [email protected]. It's free! Email Checker validates an email address in seconds.
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Xmatters
help.xmatters.com โ€บ ondemand โ€บ trial โ€บ valid_email_format.htm
Valid email address format
A valid email address consists of an email prefix and an email domain, both in acceptable formats.
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AbstractAPI
abstractapi.com โ€บ api guides, tips & tricks โ€บ how to check if an email address is in a valid format
How To Check If An Email Address Is In A Valid Format
June 24, 2025 - However, many email services limit which symbols are acceptable to ensure consistency and avoid errors. For reliable validation, it's best to accept only the more commonly used characters listed above. ... Invalid: [email protected] or [email protected]. Consecutive periods are not allowed in the local part ... Spaces and most punctuation marks (e.g., #, !, %) are not permitted. If an address contains a space or unsupported character, it's considered an invalid format.
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Clearout
clearout.io โ€บ clearout: bulk email validation & email verification service | email verifier, email finder and email tester โ€บ what is a valid email address format?
What is a Valid Email Address Format - Clearout
March 13, 2025 - Email validation is the process of determining the deliverability and validity of an email address. It entails employing various methods, such as syntax checking, typo checking, SMTP verification, and so on. It makes it simple to detect and eliminate bogus email addresses. As a result, you can keep your mailing list clean by including only valid email addresses.
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Campaign Refinery
campaignrefinery.com โ€บ what-is-a-valid-email-address
What is a Valid Email Address?
January 6, 2025 - This method might work if you have fewer emails to test โ€” type the recipient email address in Google, and it should show if itโ€™s valid. People use their email addresses publicly, which makes it easier to sweep through the database and find an existing email address. Having a recipient list with a valid gmail address or valid email IDs in general can help you land in Gmailโ€™s primary inbox instead of the spam folders.
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Webbula
webbula.com โ€บ home โ€บ what email addresses are valid?
What email addresses are valid? | Webbula
September 12, 2024 - One way to do it is by sending an email and seeing if it bounces, but this can take a while. Another option is to use an Email Address Validation tool like Webbula to ensure you have a valid email address list.
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Scribd
scribd.com โ€บ document โ€บ 698618502 โ€บ 41-Verified-Email-List-1
41 Verified Email List | PDF | Email | Online Services
The document contains results from validating email addresses and their domains. It lists 50 email addresses, their associated domain (e.g. gmail.com, yahoo.com), and whether they contained a valid MX record and domain pattern.
Rating: 5 โ€‹ - โ€‹ 2 votes
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MailerCheck
mailercheck.com โ€บ email list verification & deliverability testing tool โ€บ articles โ€บ how to check for valid vs. invalid email addresses
8 Proven Ways to Check if an Email is Valid or Invalid - MailerCheck
The best way to do this is to just ask the subscriber to confirm their email address. If any emails are delivered, give them a few days to confirm. You can then remove any subscribers who don't confirm from your list.
Published ย  June 17, 2025
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Hunter
hunter.io โ€บ email-verifier
Email Verifier: Free email checker to avoid risky email addresses โ€ข Hunter
Below is a description of all email checks performed by the Email Verifier on every email address: Valid format: First, we validate the format of the email address is correct and looks something like [email protected].
Rating: 4.5 โ€‹ - โ€‹ 1.58K votes