How Can I Verify an Email Address Exists Without Sending an Email?

Verifying Email Addresses Without Sending Emails

Question:

How can one determine if an entered email address actually exists without sending an email?

Answer:

Method 1: VRFY Command

Some SMTP servers support the VRFY command. Issuing this command followed by the email address (e.g., "VRFY example@domain.com") can verify the existence of the recipient. A positive response (DSN code 2.0.0) indicates that the user exists.

Method 2: RCPT Command

Another approach involves issuing an RCPT command, followed by the email address being checked. A 5.1.1 DSN response signifies that the email address does not exist. However, it's important to note that some servers silently discard such requests or may have limitations in verifying the existence of users.

Additional Considerations:

• Greylisting: This antispam technique can cause the rejection of initially sent emails.
• REGEX Validation: Basic regular expressions can be used to exclude obviously invalid email addresses.
• Email Verification Link: Sending an actual email with a verification link is a recommended approach, as it both validates the existence of the email address and ensures its belonging to the user who entered it.

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