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How to check pointer or interface is nil or not in Golang?

Last Updated : 12 Jul, 2025
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In Golang, nil check is frequently seen in GoLang code especially for error check. In most cases, nil check is straight forward, but in interface case, it's a bit different and special care needs to be taken. Here the task is to check pointer or interface is nil or not in Golang, you can check with the following: Example 1: In this example, the pointer is checked whether it is a nil pointer or not. C 
// Go program to illustrate how to
// check pointer is nil or not

package main

import (
    "fmt"
)

type Temp struct {
}

func main() {
    var pnt *Temp // pointer
    var x = "123"
    var pnt1 *string = &x

    fmt.Printf("pnt is a nil pointer: %v\n", pnt == nil)
    fmt.Printf("pnt1 is a nil pointer: %v\n", pnt1 == nil)
}
Output: 
pnt is a nil pointer: true
pnt1 is a nil pointer: false
Example 2: In this example, the interface is checked whether it is a nil interface or not. C 
// Go program to illustrate how to
// check interface is nil or not

package main

import (
    "fmt"
)

// Creating an interface
type tank interface {

    // Methods
    Tarea() float64
    Volume() float64
}

type myvalue struct {
    radius float64
    height float64
}

// Implementing methods of
// the tank interface
func (m myvalue) Tarea() float64 {

    return 2*m.radius*m.height +
        2*3.14*m.radius*m.radius
}

func (m myvalue) Volume() float64 {

    return 3.14 * m.radius * m.radius * m.height
}

func main() {

    var t tank
    fmt.Printf("t is a nil interface: %v\n", t == nil)

    t = myvalue{10, 14}

    fmt.Printf("t is a nil interface: %v\n", t == nil)

}
Output: 
t is a nil interface: true
t is a nil interface: false
Example 3: In this example, the interface holding a nil pointer is checked whether it is a nil interface or not. C 
// Go program to illustrate how to
// check interface holding a nil
// pointer is nil or not

package main

import (
    "fmt"
)

type Temp struct {
}

func main() {

    // taking a pointer
    var val *Temp

    // taking a interface
    var val2 interface{}

    // val2 is a non-nil interface
    // holding a nil pointer (val)
    val2 = val

    fmt.Printf("val2 is a nil interface: %v\n", val2 == nil)

    fmt.Printf("val2 is a interface holding a nil"+
            " pointer: %v\n", val2 == (*Temp)(nil))
}
Output: 
val2 is a nil interface: false
val2 is a interface holding a nil pointer: true

S

shubhamsingh10
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