How to Pad a String in Go (Left and Right)

Use strings.Repeat to generate padding and concatenate it with your string, or use fmt.Sprintf with width specifiers for a cleaner approach.

import "fmt"

s := "hello"

// Left pad to 10 chars with spaces
leftPadded := fmt.Sprintf("%10s", s)

// Right pad to 10 chars with spaces
rightPadded := fmt.Sprintf("%-10s", s)

// Custom padding (e.g., zeros)
leftZero := fmt.Sprintf("%010s", s)

For manual control without fmt, calculate the needed length and use strings.Repeat:

import "strings"

s := "hello"
width := 10
pad := " "

// Left pad
leftPadded := strings.Repeat(pad, width-len(s)) + s

// Right pad
rightPadded := s + strings.Repeat(pad, width-len(s))

Padding adds characters to the start or end of a text string to make it a specific length. You use this to align data in tables or ensure fixed-width formats for files. Think of it like adding blank space to the left or right of a word so it fits perfectly in a box.