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Basic email address format requirement.

1. Convert all upper case to lowercase.
2. Strip the spaces.
3. Remove all spaces.
4. The length must be more than 6 characters.

❌ Examples of Incorrect Email Addresses

Wrong Email Address	What’s Wrong With It
john.doe@	Missing domain name after @
@example.com	Missing local part before @
john.doe@example	Missing top-level domain (e.g., .com, .org)
john..doe@example.com	Double dots in the local part are not allowed
john.doe@.com	Domain name cannot start with a dot
john.doe@com.	Domain name cannot end with a dot
john.doe@exam!ple.com	Special characters like ! are not allowed in domain
john doe@example.com	Spaces are not allowed in email addresses
john.doe@example..com	Double dots in domain part are invalid
john.doe@.example.com	Domain cannot start with a dot

Advanced detail requirements

✅ 1. Local Part (before the @)

• Can include:
  • Letters (A–Z, a–z)
  • Digits (0–9)
  • Special characters: ! # $ % & ' * + - / = ? ^ _ { | } ~`
  • Dots (.), but not at the beginning or end, and not consecutively
• Cannot include:
  • Spaces
  • Special characters like (),:;<>@[\]
• Max length: 64 characters

Examples (valid):

• john.doe
• user_name123
• first.last+tag

✅ 2. @ Symbol

• Must be present exactly once
• Separates the local part from the domain

✅ 3. Domain Part (after the @)

• Must include:
  • A domain name (e.g., example)
  • A top-level domain (TLD) like .com, .org, .net
• Can include:
  • Letters, digits, hyphens (-)
• Cannot:
  • Start or end with a hyphen
  • Have consecutive dots
• Max length: 255 characters

Examples (valid):

• example.com
• teachonetofish.net