What a flowchart is and why you need one

A flowchart is a diagram that shows the steps in a process using boxes, diamonds, and arrows. Each shape means something different — rectangles hold actions, diamonds hold decisions (yes/no questions), and arrows show which step comes next. Flowcharts let you see the whole path at once instead of reading it in words.

You use flowcharts to plan before you build, to explain how something works to someone else, or to find where a process breaks down. A manager might draw one to show how a customer order moves through the company. A programmer might draw one to plan code before writing it. A teacher might draw one to show students the steps in solving a math problem.

The real value is that flowcharts force you to think through every step and every choice. When you have to draw it, you notice the gaps.

Key Takeaways

  • Start by listing every step and decision in your process, in order, before you draw anything.
  • Use rectangles for actions, diamonds for yes/no decisions, ovals for start and end, and arrows to connect them.
  • You can draw flowcharts by hand on paper, in free tools like Google Drawings or Lucidchart, or in Microsoft Visio if your workplace has it.
  • Keep each box short — one phrase, not a sentence — so the flowchart stays readable.
  • Test your flowchart by following it step-by-step to make sure every path leads somewhere and nothing loops forever.

Plan your flowchart before you draw

The biggest mistake is opening a drawing tool and starting to sketch. Instead, spend five minutes writing down the process in plain language first. Write every step, every choice, and every possible outcome. Do not worry about order yet — just dump it all out.

Then number the steps in the order they actually happen. Mark the places where the process branches — where someone makes a choice and the next step depends on that choice. Mark where the process ends. If the process can loop back (like "try again" or "repeat until done"), mark that too.

This list is your blueprint. When you move to the drawing tool, you are just translating what you already planned.

Learn the shapes and what they mean

Flowchart shapes are standardized, so anyone who reads one will understand it the same way. You only need five shapes for most flowcharts:

  • Oval or rounded rectangle: Start or end. Write "Start" or "End" inside.
  • Rectangle: An action or step. Write what happens — "Send email", "Check inventory", "Enter data".
  • Diamond: A decision or question with a yes/no answer. Write the question inside — "Is the order over $100?" or "Does the file exist?"
  • Arrow: Shows the direction of flow. Points from one shape to the next. Label it if needed — "Yes" or "No" from a diamond, or "If approved" from a rectangle.
  • Parallelogram (optional): Input or output, like "Receive order" or "Print report". Many people just use rectangles instead.

Stick to these five. Fancy shapes distract from the logic. The goal is clarity, not decoration.

Draw your flowchart step by step

Open your drawing tool — Google Drawings (free, in Google Drive), Lucidchart (free tier available), or Visio if you have it. Start at the top with an oval labeled "Start".

Below it, add your first action in a rectangle. Draw an arrow from Start to that rectangle. Then add the next step, and the next, moving down the page. Each rectangle gets an arrow pointing to the next one.

When you reach a decision, switch to a diamond. Write the question inside. Draw two arrows out of it — one labeled "Yes" going to the next step if the answer is yes, one labeled "No" going to the next step if the answer is no. Those two paths may rejoin later, or they may stay separate.

Keep going until every path reaches an oval labeled "End". If a path loops back (like "try again"), draw an arrow that curves back to an earlier step. Make sure every path eventually ends — nothing should loop forever without a way out.

Keep your flowchart readable

A flowchart that is hard to follow defeats the purpose. Write as few words as possible in each box — three words maximum. "Check inventory" is better than "Check to see if the item is in stock". "Is stock > 0?" is better than "Determine whether the quantity on hand exceeds zero".

Arrange shapes so arrows do not cross each other. If you have a lot of crossing, redraw it — move shapes around until the flow is clearer. Arrows should mostly go down the page, with branches to the left or right when needed.

Use consistent spacing. Line up shapes vertically when they are at the same level. This makes the diagram look organized and easier to scan. If your tool has a grid or alignment guides, turn them on.

If your flowchart gets very long or very wide, break it into smaller flowcharts. One flowchart per major process is easier to understand than one giant chart that covers everything.

Test your flowchart by walking through it

Before you share it or use it, follow the flowchart as if you were actually doing the process. Start at "Start" and follow the arrows. At each decision diamond, pick an answer (yes or no) and follow that arrow. Keep going until you reach "End".

Then do it again with a different choice at the decision points. Try to follow a path that should fail or loop. Does the flowchart handle it correctly, or does it get stuck?

Ask yourself: Does every box lead somewhere? Does every path eventually end? Is there any step that does not make sense? Are there any steps missing? If you find a problem, fix it now before anyone else uses the flowchart.

Tools you can use to draw flowcharts

Google Drawings is free and works in any web browser. Open Google Drive, click "Create", choose "Drawing", and start adding shapes. It has flowchart shapes built in, and you can share the drawing with others. The downside is that it is slower for large or complex flowcharts.

Lucidchart has a free tier that lets you create three flowcharts. It is faster than Google Drawings and has more flowchart templates to start from. You can export as an image or PDF. The paid version removes the limit.

Microsoft Visio is the industry standard for flowcharts, but it costs money and is only available on Windows and Mac. If your workplace has it, use it — it is built for this. If not, the free tools are good enough.

Draw.io (also called Diagrams.net) is free, open-source, and works in your browser or as a desktop app. It has all the shapes you need and is very fast. You can save to your computer or to cloud storage.

For a simple flowchart, paper and pencil work fine. Draw the shapes freehand, label them, and take a photo. You can always redraw it in a tool later if you need to share it.

Frequently Asked Questions

What if my process has more than two choices at one point?

Use multiple diamonds in a row. The first diamond asks one yes/no question and branches into two paths. If one of those paths needs to ask another question, add another diamond on that path. Each diamond should have exactly two arrows out of it — one for yes, one for no.

Can I use different colors for different types of steps?

Yes. Many people color-code flowcharts — for example, all actions in blue, all decisions in red, all endpoints in green. This makes it easier to scan. Just pick a scheme and stick with it so it is consistent.

What if the flowchart is too big to fit on one page?

Break it into smaller flowcharts. Create one flowchart for the main process, then separate flowcharts for each major decision or branch. Label them clearly so someone knows which one to read next. You can also print it on multiple pages or zoom out to see the whole thing at once.

How do I show that something happens at the same time as something else?

Standard flowcharts show steps in order, one after another. If you need to show parallel processes (things that happen at the same time), use a different diagram type called a swimlane diagram. Each lane is a person or system, and you can show what each one does at the same time. This is more advanced — start with a simple flowchart first.

Should I add more details or keep it simple?

Keep it simple. The goal is to show the main path and the main decisions. If you add too much detail, the flowchart becomes hard to read. If someone needs more detail, they can ask — you can always create a second flowchart that zooms in on one part.