Searching a Slice

In this lesson you will learn the basic way to search within a slice in Go so you can check whether a value is present. This is for anyone searching for "Go slice search how to".

Go has no simple built-in "does it contain this" function, so the basic approach is to loop with for and compare items one at a time.

The sample code examines the slice item by item with for _, f := range fruits and sets found to true when the condition f == "orange" holds. Go 1.21 and later also added the handy slices.Contains to the standard library, which is shorter still.

A common stumbling block for beginners is performance with larger data sets. Comparing one at a time in a for loop is easy to read, but a map-based lookup is faster once there is a lot of data, so pick to suit the job.

In real-world development this search comes up whenever you need to confirm that a list contains a particular product ID or user name.

📖 Reference code

package main

import "fmt"

func main() {
    fruits := []string{"apple", "orange", "grape"}
    found := false
    for _, f := range fruits {
        if f == "orange" {
            found = true
        }
    }
    fmt.Println(found)
}

✍️ Your code

Type your code, then press "Run"

🧪 This site can't compile or run Go directly, so it checks on the spot whether what you typed matches the reference code (scoring happens entirely in your browser — nothing is sent anywhere).