Go Slices - The Basics

A slice is a bit like a dynamic array in other languages. Unlike a standard Go Array, slices can have items added and removed items from them as shown in the example below.

Planets Example

Create the slice

To create an empty slice to hold a list of strings, you can do the following. Note how we do not include any size:

planets := []string{}

To add items to the slice, we use the built-in 'append' function:

planets = append(planets, "Moon")
planets = append(planets, "Mercury")
planets = append(planets, "Mars")

// Here we add two items at once
planets = append(planets, "Jupiter", "Venus")

Looping through the slices

Just like with arrays, we can use a for loop to read through the values:

// Each value is taken from the planets slice and put into the 'v' variable.
for _, v := range planets {
	fmt.Println(v)
}

Removing an item from the slice

Removing is a little trickier, we can the Delete function from the 'slices' package and give it a range to delete. In the block below, start is the first item we want to delete, end is one higher than the last item to delete e.g.

// If our slice contains:
// 0 = Moon
// 1 = Mercury
// 2 = Mars
// 3 = Jupiter
// 4 = Venus
// To delete items 2 and 3 we would do the following:

planets = slices.Delete(planets, 2, 4)

Full Go Program

The Go compiling guide explains the folder set up for a Go program, once that is done:

• Save the following into the project folder as planets.go
• From the command line, inside the folder use go build to make your exe file.
• Run the compiled program with planets

package main

import (
	"fmt"
	"slices"
)

func main() {
	planets := []string{}

	// Adding to the 'planets' slice
	planets = append(planets, "Moon")
	planets = append(planets, "Mercury")
	planets = append(planets, "Mars")
	planets = append(planets, "Jupiter", "Venus")

	// Show our planets (and moon)
	for _, v := range planets {
		fmt.Println(v)
	}
	
	// Delete Mars and Jupiter, items 2 and 3
	planets = slices.Delete(planets, 2, 4)
	
	// Show our planets (and moon)
	for _, v := range planets {
		fmt.Println(v)
	}
	
}

Updated (25/08/2026)