The FormattedInput component for Blazor enables changing the numeric system of the displayed number by choosing an option from the dropdown. The component can be initialized from an HTML input and provides validation. When the user enters a number whose decimal equivalent is not from 0 to 1000, the FormattedInput updates the number to the chosen numeral system's equivalent of 0 or 1000 depending on whether the number's decimal equivalent is below 0 or above 1000.