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For US Zip code validation Use below regular Expression. ^([0-9]{5})$. For Canada Postal code validation Use below regular Expression to validate the zip/postal code in your form. ^[ABCEGHJKLMNPRSTVXYabceghjklmnprstvxy]{1}\d{1}[A-Za-z]{1} *\d{1}[A-Za-z]{1}\d{1}$.
The basic format consists of five decimal numerical digits. An extended ZIP+4 code, introduced in 1983, includes the five digits of the ZIP code, a hyphen, and four additional digits that determine a more specific location within a given ZIP code. The USPS provides a free online lookup tool for ZIP codes.