• VLOOKUP Function: Similar to its Excel counterpart, the VLOOKUP function lets you use data in another object as a basis for validation. For example, to validate the zip code in a contact address, you could use the VLOOKUP function in a contact validation rule to search for a match in a custom object containing a list of valid zip codes.
• ISNUMBER Function: The ISNUMBER function provides a simple way to tell if data entered in a text field only contains numbers, which is required for many types of identification numbers like credit cards and account numbers.
• REGEX Function: Regular expressions are a powerful tool used by programmers to find patterns within bodies of text. The REGEX function exposes the power of regular expressions in validation rules, empowering formula authors to tackle the most demanding format validation challenges. Need to validate an IP address, country-specific phone number or VAT number format? If so, the REGEX function is for you.

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