How to compare two slices of bytes in Golang? (original) (raw)

Last Updated : 12 Jul, 2025

In Go, a slice is a powerful, flexible data structure that allows elements of the same type to be stored in a variable-length sequence. When working with byte slices ****(** []byte ), Go provides easy-to-use functions in the bytes package to compare them. In this article we will learn "How to compare two slices of bytes in Golang".

**Example

slice1 := []byte{'G', 'o', 'l', 'a', 'n', 'g'} slice2 := []byte{'G', 'o', 'l', 'a', 'n', 'g'} slice3 := []byte{'g', 'o', 'L', 'A', 'N', 'g'}

Syntax

**func Compare(a, b []byte) int #bytes.Compare() **func Equal(a, b []byte) bool #bytes.Equal() **func DeepEqual(x, y interface{}) bool #reflect.DeepEqual()

Table of Content

• Comparing with bytes.Compare()
• Comparing with bytes.Equal()
• Using reflect.DeepEqual() (Alternative Method)

Comparing with bytes.Compare()

The bytes.Compare function returns:

• **0**if the slices are **equal,
• **-1**if slice1 is **less than slice2, and
• 1 if slice1 is greater than slice2.

Syntax

**func Compare(a, b []byte) int

**Example:

Go `

package main import ( "bytes" "fmt" )

func main() { slice1 := []byte{'G', 'o', 'l', 'a', 'n', 'g'} slice2 := []byte{'G', 'o', 'l', 'a', 'n', 'g'} slice3 := []byte{'g', 'o', 'L', 'A', 'N', 'g'}

fmt.Println(bytes.Compare(slice1, slice2)) // Output: 0 (equal)
fmt.Println(bytes.Compare(slice1, slice3)) // Output: -1 (slice1 < slice3)

}

`

Comparing with bytes.Equal()

To directly check if two byte slices are equal, use bytes.Equal, which returns true if the slices are identical.

**Syntax

func Equal(a, b []byte) bool

**Example

Go `

package main import ( "bytes" "fmt" ) func main() { slc1 := []byte{'G', 'o', 'l', 'a', 'n', 'g'} slc2 := []byte{'G', 'o', 'l', 'a', 'n', 'g'} slc3 := []byte{'g', 'o', 'L', 'A', 'N', 'g'}

fmt.Println(bytes.Equal(slc1, slc2)) // Output: true
fmt.Println(bytes.Equal(slc1, slc3)) // Output: false

}

`

Using reflect.DeepEqual() (Alternative Method)

reflect.DeepEqual compares the values and structure of two variables. While not specific to byte slices, it can also be used for equality checks.

Syntax

func DeepEqual(x, y interface{}) bool

**Example

Go `

package main import ( "fmt" "reflect" ) func main() { slc1 := []byte{'G', 'o', 'l', 'a', 'n', 'g'} slc2 := []byte{'G', 'o', 'l', 'a', 'n', 'g'} slc3 := []byte{'g', 'o', 'L', 'A', 'N', 'g'}

fmt.Println(reflect.DeepEqual(slc1, slc2)) // Output: true
fmt.Println(reflect.DeepEqual(slc1, slc3)) // Output: false

}

`