Golang Make and New Keywords

Introduction

If you have started learning golang then it's very obvious that you must be aware of Golangs keywords. Golang's Keywords that we will be learning today are used for the instantiation of items.

What is the "make" Keyword?

"make" in Golang is a keyword that is used to initialize only slices, maps, and channels. Unlike the new keywords, it does not return the pointer to the item. It initializes the data in memory with zero value.

Example:

In a case where the slice is created with the make keyword, the underlying array will be created and memory will be assigned to it with a specified length and capacity.

Transform Your Career

Choose from our industry-leading programs designed for career success

NSDC Certified

Modern Software and AI Engineering Program

Master full-stack development with AI integration

12 MonthsDuration

AI-LedCurriculum

Career SupportSupport

+1000 more

Go to Program

NSDC Certified

Modern Data Science and ML with specialisation in AI

Advanced data science techniques with AI specialization

12 MonthsDuration

AI-LedCurriculum

Career SupportSupport

+1000 more

Go to Program

NSDC Certified

Advanced AIML with Specialisation in Agentic AI

Deep dive into AIML with focus on Agentic systems

12 MonthsDuration

AI-LedCurriculum

Career SupportSupport

+1000 more

Go to Program

NSDC Certified

DevOps, Cloud & AI Platform Engineering

Build and manage AI-powered cloud infrastructure

12 MonthsDuration

AI-LedCurriculum

Career SupportSupport

+1000 more

Go to Program

NSDC Certified

AI Engineering Advanced Certification by IIT-Roorkee

Premier AI engineering certification from IIT-Roorkee

3 MonthsDuration

AI-LedCurriculum

Career SupportSupport

Go to Program

What is a "new" Keyword?

"new" in Golang is a keyword that is used to instantiate a struct (custom data type). The new keyword returns a pointer to the instantiated variable. It creates a "zeroed" storage for a new item.

Example:

In a case where we create a slice using a new keyword, the underlying array won't be created. thus new([]int) returns a pointer to nothing

What is the Difference between "make" and "new"?

1. make in Golang is only used to allocate and initialize data of slice, map, and chan. new can assign any type of data(including slice, map, chan, and any custom struct)
2. new returns a pointer of newly created data and make returns value of those.
3. new just allocates memory, not initializes memory whereas make allocates and initializes memory.

Examples of "make"

Create Slice Using "make"

The below code shows how we can create slices. The first way to create a slice is based on parameters like length and capacity, giving us more flexibility. The second example creates a slice of a specified size.

Output:

Try on Playground.

Create Map Using "make"

Now let's create a map using the make keyword. We will first initialize the map and then assign values to it. Once a map is created we will add keys and values to it.

Output:

Try on Playground.

Create Channel Using "make"

Lastly, we will create a Golang Channel using make, once the channel is created we will add a message to it and later print it on the console.

Output:

Try on Playground.

Examples of "new"

Create Struct Using "new" Keyword

new returns a pointer to the struct. Each field inside the struct can then be accessed and modified.

We created a vehicle struct and later initialized it with the new keyword in golang. After the initialization, we assigned the values to the fields and later printed those to the console.

Output:

Try on Playground.