Guides
What is a flowchart?
A flowchart is a diagram that shows the steps of a process in order, using standard shapes for actions and decisions and arrows for the direction of the flow. It turns a procedure that is hard to follow in text into a path anyone can trace with a finger.
A short definition
A flowchart represents a process as a sequence of steps connected by arrows. Each step uses a shape that tells you what kind of step it is: an oval for the start and the end, a rectangle for an action, a diamond for a question with several possible answers. Read it from the start, follow the arrows, and at every diamond take the branch that matches your situation.
The idea is older than computers. Frank and Lillian Gilbreth presented their "flow process chart" to engineers in 1921 to analyse factory work, and programmers later adopted flow diagrams to plan their code. Today the same notation describes customer journeys, approval circuits, support procedures and software logic.
What flowcharts are used for
- Explaining a procedure to a new colleague without a wall of text.
- Agreeing on how work really happens before changing it, which is the starting point of process mapping.
- Spotting problems: loops that never end, decisions nobody owns, steps that wait for no reason.
- Designing logic for software, from a sign-up form to an algorithm.
- Documenting a process in a wiki, a README or a quality manual.
How to read a flowchart
- Find the start shape, usually an oval at the top or on the left.
- Follow the arrows. A flowchart has one direction of reading, most often top to bottom.
- At a diamond, read the question and follow the arrow labelled with your answer, such as "Yes" or "No".
- Stop when you reach an end shape. A good flowchart has no dead ends: every path finishes somewhere.
If a chart uses columns with a name at the top, each column is the responsibility of one person, team or system. That variant is called a swimlane diagram.
The building blocks
Most flowcharts only need five or six shapes. The guide to flowchart symbols explains each one and when to use it. Decisions deserve special care because they create branches and loops: see how to draw decisions and loops.
Depending on what you describe, you will pick a different kind of chart: a simple process flowchart, a swimlane diagram, a data flow diagram or an algorithm flowchart. The overview of types of flowcharts helps you choose.
Drawing your own
You can draw a flowchart on paper, in a diagramming tool, or as text in Mermaid. The method is the same in every case and is detailed step by step in how to make a flowchart. Before sharing it, run through the list of common flowchart mistakes.
If you already know how the process works, the fastest route is to describe it in a few sentences and let an AI flowchart generator draw the first version, which you then correct.
When a flowchart is not the right tool
A flowchart shows order and decisions. It is a poor fit for showing how parts of a system are structured (use an architecture diagram), how data is organised (use an entity-relationship diagram), or a project schedule (use a Gantt chart). For processes that must be executed by a workflow engine, a formal notation such as BPMN may be required: the comparison flowchart vs BPMN explains the difference.
In this guide
Each article goes deeper into one part of the topic.
- Flowchart symbols and their meaningFive symbols cover most flowcharts: the oval (start or end), the rectangle (an action), the diamond (a decision), the parallelogram (input or output) and the arrow (the order of steps). The others are useful in specific cases, such as documents, databases or waiting times.
- How to make a flowchart, step by stepTo make a flowchart, define where the process starts and ends, list the steps in order, add the decisions and their branches, assign each step to an owner, connect everything with arrows, then review the chart with someone who does the work.
- Types of flowcharts and when to use eachChoose the type of flowchart from the question you want to answer: a process flowchart shows the order of steps, a swimlane diagram shows who does what, a data flow diagram shows where information goes, and an algorithm flowchart shows the logic of a program.
- Decisions, branches and loops in a flowchartA decision is a diamond containing a question, with one labelled arrow per possible answer. Every branch must lead to a step or an end, and every loop needs an exit condition, such as a maximum number of attempts or a timeout.
- Common flowchart mistakes and how to fix themMost flowchart problems come from three sources: missing paths (dead ends, unlabelled branches, loops without exits), unclear wording (vague steps, questions that cannot be answered) and too much on one chart. Each has a simple fix.
Turn your process into a flowchart
Describe it in a few sentences. Flowchartio draws the flowchart, then you refine it in conversation.
Generate a flowchart