Golang: How to pad a number with zeros when printing?

Question

How can I print a number or make a string with zero padding to make it fixed width?

For instance, if I have the number 12 and I want to make it 00

Answer 1

There is one simplest way to achieve this. Use

func padNumberWithZero(value uint32) string {
    return fmt.Sprintf("%02d", value)
}

fmt.Sprintf formats and returns a string without printing it anywhere. Here %02d says pad zero on left for value who has < 2 number of digits. If given value has 2 or more digits it will not pad. For example:

• If input is 1, output will be 01.
• If input is 12, output will be 12.
• If input is 1992, output will be 1992.

You can use %03d or more for more zeros padding.