Print Binary of Number in C

  1. Binary Number System
  2. C Implementations for Conversion

This trivial guide is about implementing decimal to binary number system converter using the C language. Before jumping into the implementation directly, we will first recap the binary number system and then discuss multiple C implementations to convert a decimal representation into a binary equivalent.

Binary Number System

Any system which operates on two discrete or categorical states is known as a binary system. Similarly, a binary number system represents numbers using only two symbols: 1 (one) and 0 (zero).

Therefore, it is also known as the base-2 system.

Currently, most transistor-based logic circuit implementations use discrete binary states. Therefore, all modern digital computers use binary systems to represent, store, and process data.

For example, converting 6 into a binary number system.

$$ (6)_{10} = (110)_2 $$

Here, 6 is the number from the decimal number system with base 10, and its corresponding binary is 110, which is in the binary number system having base 2. Let’s look at the process of this conversion.

Process of Conversion

Step 1: Dividing 6 by 2 to get the answer. You get the dividend for the next step, using the integer quotient achieved in this stage.

Continue in this manner until the quotient reaches zero.

Dividend Remainder
62 = 3 0
32 = 1 1
12 = 0 1

Step 2: The binary can be formed by collecting all the remainders in reverse chronological order (from bottom to top).

With 1 being the most significant bit (MSB) and 0 being the least significant bit (LSB). Hence, the binary of 6 is 110.

C Implementations for Conversion

There can be multiple ways in the C language to convert a number into a binary number system. It can be an iterative solution or a recursive one.

It is up to your choice of programming. This article will discuss a recursive solution because it is very straightforward.

Solution 1:

If number > 1:

  1. place number on the stack
  2. call function with number/2 recursively
  3. Take a number from the stack, divide it by two, and output the remainder.
#include <stdio.h>

void convertToBinary(unsigned a)
    /* step 1 */
    if (a > 1)
        convertToBinary(a / 2);

    /* step 2 */
    printf("%d", a % 2);
int main() {
    // Write C code here
    printf("Binary of the number is: ");

    return 0;

This code snippet releases the following output.

Binary of the number is: 110

Solution 2:

  1. Check if number > 0
  2. Apply the right shift operator by 1 bit and then call the function recursively.
  3. Output the bits of the number
#include <stdio.h>
void convertToBinary(unsigned n)
    if (n > 1)
        convertToBinary(n >> 1);

    printf("%d", n & 1);
int main() {
    // Write C code here
    printf("Binary of the number is: ");

    return 0;

The output of the given code snippet is:

Binary of the number is: 1000
Write for us
DelftStack articles are written by software geeks like you. If you also would like to contribute to DelftStack by writing paid articles, you can check the write for us page.