Go Arithmetic Operators – Perform Math Operations in Go (2025 Guide)

Introduction – Why Arithmetic Operators Matter in Go

Arithmetic operators are used to perform mathematical calculations like addition, subtraction, multiplication, division, and modulo. Whether you’re building a calculator, processing data, or performing logic in backend systems, mastering Go’s arithmetic operators is foundational.

In this section, you’ll learn:

• The full list of arithmetic operators in Go
• Syntax rules with examples and outputs
• How Go handles integer vs float division
• Real-world usage and operator precedence

List of Arithmetic Operators in Go

Syntax – Using Arithmetic Operators in Go

package main

import "fmt"

func main() {
    a := 15
    b := 4

    fmt.Println("Addition:", a+b)
    fmt.Println("Subtraction:", a-b)
    fmt.Println("Multiplication:", a*b)
    fmt.Println("Division:", a/b)
    fmt.Println("Modulo:", a%b)
}

Output:

Addition: 19
Subtraction: 11
Multiplication: 60
Division: 3
Modulo: 3

Note: Division between two integers always produces an integer result (truncated).

Float Division Example

x := 10.0
y := 4.0
fmt.Println(x / y)  // Output: 2.5

If either operand is a float, the result will be a floating-point value.

Type Mismatch: Must Match Types

You cannot mix int and float64 directly:

var a int = 5
var b float64 = 2.5
// fmt.Println(a + b)  Compile-time error

Fix:

fmt.Println(float64(a) + b)

Example – Arithmetic Expression

a, b, c := 10, 3, 2
result := a + b*c - a/b
fmt.Println(result)

Breakdown:

a + (b * c) - (a / b)
10 + 6 - 3 = 13

Output:

13

Operator Precedence in Go

Use parentheses () to override precedence for complex expressions.

Summary – Recap & Next Steps

Go’s arithmetic operators are straightforward but require attention to types and division behavior. These operators are frequently used in algorithms, loops, and conditions.

Key Takeaways:

• Use +, -, *, /, % for basic arithmetic
• Integer division discards the decimal part
• Use float64 for precise division
• Match operand types before performing operations
• Use parentheses to control order of operations

Next: Explore Relational Operators in Go to compare values using ==, !=, <, > and more.

FAQs – Arithmetic Operators in Go

What happens when I divide two integers in Go?
Go returns an integer result. The decimal part is truncated.

How do I perform floating-point division?
Use float32 or float64 operands:

fmt.Println(10.0 / 4.0) // Output: 2.5

Can I use arithmetic operators on strings or booleans?
No. Arithmetic operators only work with numeric types (int, float, complex).

What does % (modulo) return?
It returns the remainder of an integer division: 10 % 3 = 1

How can I change precedence in an expression?
Use parentheses to group operations:

result := (a + b) * c