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C is one of the most common programming languages in the technology world. It is the language responsible for creating many familiar applications and games, including Doom, Quake, Windows (early versions), Linux kernels, and countless more.

Flowcharts are essential and most popular tools when learning a programming language, including C. Looking for a complete guide to creating a simple flowchart in C? What to find out what is a flowchart in programming? You have come to the right place!

We will show you all you need to know about the flowchart in C. Without further delay, let’s dive right into it!

What Is A Flowchart?

Flow charts are diagrams showing the exact sequence of logical steps. They use geometrical shapes and arrows to show processes, relationships, and data/process flow. In other words, flowcharts depict decisions and results of them. 

In different fields, flowcharts are often used to analyze and manage processes. To put it simply, it helps you visualize what the processes look like. That way, you can see all the bottlenecks and flaws in them. The act of creating a chart is called flowcharting.

Flowchart In C Programming

Flowcharts are useful tools in software development. In C programming, flowcharts are often used to represent algorithms or programs. They show the connections, flow of information, and processes within an algorithm or a program. For example, here's an if else flowchart that's often used in C programming.

Programmers use flowcharts in the program-planning, or the debugging process, often to solve problems, even in complex programs. 

A program might contain many flows of logic and processes, so flowcharts, using natural language and symbols, can also help normal, non-technical people understand how the program works. Here are some conventional symbols for a basic flowchart:

flowchart symbols
Flowchart Symbols


Here are some simple examples of flowcharts related to C programming: 

Example 1: Print “Hello World.” On-screen

When you first learn a programming language, whether Python, Pascal, or C, your first program is often a simple “Hello World” program. So, a chart of a simple program of printing a “Hello World” message onto the screen should be like this:

Print "Hello World" on screen algorithm flowchart
Print "Hello World" on screen Flowchart

Example 2: Calculate The Average Of Two Numbers.

As you may have already known, to calculate the average of two numbers, you can sum up those two numbers and divide the result by 2. In other words, the formula for calculating the average of two numbers is: (number 1 + number 2)/2. 

So the basic shapes of the chart should be like this:

Calculate The Average Of Two Numbers algorithm flowchart

Example 3: Input Number And Check If They Are Odd Or Even

Another relatively simple program is checking odd/even numbers. It is a basic conditional operation that involves: inputting a number, determining whether it is odd or even, printing the result on-screen. The chart should be something like this:

Input Number And Check If They Are Odd Or Even Algorithm Flowchart
Input Number and Check If They Are Odd or Even Algorithm Flowchart

Example 4: Controlling Algorithm For Toaster

There will be two inputs for this flowchart: the button you push to start the toaster and another input to measure the toaster’s cooking temperature. 

The heater is an output, which can be on or off. Your toaster will lower the bread inside to cook when the heat is on, turn off the heat then eject the toast when it is done. The detailed chart should be as follows:

Controlling Algorithm for Toaster algorithm flowchart
Controlling Algorithm for Toaster

Flowchart Guidelines

To create a flowchart, you must follow the following current standard guideline:

  • Step 1: Start the program.
  • Step 2: Begin Process 1 of the program.
  • Step 3: Check some conditions and take a Decision (“yes” or “no”).
  • Step 4: If the decision is “yes”, proceed to Process 3. If the decision is “no”, proceed to Process 2 and return to Step 2.
  • Step 5: End of the program.
Standard Flow Chart
Building a standard flow chart

Additionally, the following can be helpful tips in creating flowcharts as well:

  • You can only have one start and one end in your chart, no more, no less.
  • On-page connectors are referred to by numbers, while off-page connectors are referred to by alphabetical letters.
  • The flow of processes is generally from top to bottom or left to right, not the other way around.
  • It would be best not to make the arrows cross each other.


It is important to plan ahead with coding. Coding is a process that can take a while and it it is best to plan ahead. One way of planning is by using a flowchart as a guide. This flowchart should indicate which blocks of code will be used where, what the codes will do, and how they will interact with each other. These are just some of the many methods programmers use to plan their coding before they even start.