---
title: 1.8 Integer Type Conversion
description: "Integer type conversion occurs when a value of one integer type is converted to another integer type. C performs these conversions implicitly in several situations, such as assignments and expressions. ``` #include int main() { char a = 10; int…"
url: "https://edcret.in/docs/c-programming/basic-refreshers/1-8-integer-type-conversion/"
updated: "2026-09-06"
category: C Programming / Basic Refreshers
---

# 1.8 Integer Type Conversion

Integer type conversion occurs when a value of one integer type is converted to another integer type. C performs these conversions implicitly in several situations, such as assignments and expressions.

```
#include <stdio.h>

int main()
{
    char a = 10;
    int b = 20;

    int result = a + b;

    printf("a = %d\n", a);
    printf("b = %d\n", b);
    printf("result = %d\n", result);

    return 0;
}
```

### Example Output

```
a = 10
b = 20
result = 30
```

### Explanation

Before the addition is performed, `a` undergoes **integer promotion**:

```
a + b
```

Since `a` is a `char`, it is promoted to `int` when `int` can represent all values of the original type. The addition is therefore performed using `int` operands.

The result of the addition is an `int`, which is stored in:

```
int result
```

### Common Integer Conversions

| Conversion | Example | Resulting type |
| --- | --- | --- |
| `char` → `int` | `char + int` | `int` |
| `short` → `int` | `short + int` | `int` |
| `char` → `unsigned int` | assignment/conversion | `unsigned int` |
| `int` → `long` | `long x = int_value` | `long` |
| `int` → `short` | `short x = int_value` | `short` |
| `int` → `char` | `char x = int_value` | `char` |

### Integer Promotion

Integer types with rank lower than `int`, such as `char` and `short`, are subject to integer promotions when used in most expressions.

```
char a = 10;
char b = 20;

int result = a + b;
```

Both `a` and `b` are promoted before the addition, so the operation is performed using `int`.

### Conversion During Assignment

Conversion also occurs when an integer value is assigned to an object of a different integer type.

```
int number = 100;
short value = number;
```

The value of `number` is converted to `short` before being stored in `value`. If the destination type cannot represent the value, the resulting value follows the rules for conversion to that integer type.

Integer conversion rules become more involved when signed and unsigned types are combined. Those cases are covered further in the type-conversion section.