What is the range of int in Java?

The range of the int data type in Java is from -2,147,483,648 to 2,147,483,647.

Understanding the int Data Type in Java

The int keyword in Java represents a fundamental primitive data type used to store whole numbers. It is a signed 32-bit two's complement integer, meaning it can store both positive and negative integer values. Understanding its range is crucial to prevent common programming errors like integer overflow or underflow.

Exact Range of int

• Minimum Value: -2,147,483,648
• Maximum Value: 2,147,483,647

These exact minimum and maximum values are also conveniently accessible in Java through the java.lang.Integer wrapper class as static constants:

• Integer.MIN_VALUE
• Integer.MAX_VALUE

Why is the Range Important?

Knowing the precise range of int is vital for several reasons:

• Preventing Overflow and Underflow: If a calculation results in a value larger than Integer.MAX_VALUE or smaller than Integer.MIN_VALUE, it leads to an overflow or underflow condition, respectively. In Java, this typically results in the value "wrapping around" to the opposite end of the range, leading to incorrect numerical results without throwing an error in most cases.
  • Example of Overflow: If 2147483647 + 1 is stored in an int, the result will be -2147483648.
• Memory Management: An int variable occupies 32 bits (4 bytes) of memory. While this is generally small, using the appropriate data type helps in efficient memory utilization, especially when dealing with large arrays or collections of numbers.
• Choosing the Correct Data Type: For numbers that might exceed the int range, Java provides the long data type, which is a signed 64-bit integer, offering a much larger range.

Comparison with Other Java Integer Types

Java offers several primitive integer data types, each with a different size and range, allowing developers to choose the most suitable one based on their application's requirements. Here's a quick comparison of int with long, which is also a signed integer type:

For more comprehensive information on Java's primitive data types, you can refer to the official Oracle documentation on primitive data types.