The TEXT function can apply number formats of any kind, including currency, date, percentage, etc. By applying a number format like "00", "000", "0000", you can "pad" numbers with as many zeros as you like. Zeros will only be added where needed.
Number format only
The TEXT function converts numbers to text as a normal step in applying the number format.
If you are concatenating (joining) the result to another text string, this is fine, but if you just want to apply visual padding to a free-standing number set of numbers, you can apply a custom number format without using a formula.
If you need to get the week number from the day from a date, you can use the WEEKNUM function. The date must be in a form that Excel recognizes as a valid date. How this formula works: The WEEKNUM function takes two arguments, a date, and,...
The Excel WEEKNUM function takes a date and returns a week number (1-54) that corresponds to the week of year. The WEEKNUM function starts counting with the week that contains January 1. By default, weeks begin on Sunday.
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