Mermaid vs draw.io vs Visio: Which Should a BA Use?
Mermaid, draw.io and Visio can all draw the same process map, but they win at different things. Build a small refund flow in the free Mermaid live editor and hear how the three tools compare on speed, looks and sharing for a business analyst.
Step by step
Three tools
- Mermaid vs draw.io vs Visio. Mermaid, draw.io and Visio can all draw a process map. To compare them, we build a small refund flow in Mermaid and look at speed, looks and sharing as we go.
Speed
- Speed. Open the free Mermaid live editor in your browser, clear the sample code and type flowchart TD. TD means top-down, so the map runs from top to bottom. In draw.io or Visio, you would open a blank page and find a set of shapes first. Type A([Refund requested]) --> B[Check receipt]. This one line makes two shapes and the arrow between them. A is a rounded start shape and B is a plain box. Add B --> C{Receipt valid?}. Curly brackets make a diamond decision shape. Then C -->|Yes| D[Refund customer] and C -->|No| E[Explain refusal] add the two paths. The text between the | signs becomes the label on each arrow. The preview draws the map for you. There is no dragging and no lining up of boxes, so for a quick map, typing is often faster than drawing. Both paths end in the same place. D --> F([Request closed]) adds one rounded end shape. E --> F sends the No path to that same shape, because F already exists.
flowchart TDA([Refund requested]) --> B[Check receipt]B --> C{Receipt valid?} C -->|Yes| D[Refund customer] C -->|No| E[Explain refusal]D --> F([Request closed]) E --> F
Looks
- Looks. Here is the whole flow. Mermaid places every shape for you. That is quick, but you can't drag one box to where you want it. In draw.io and Visio, you place every shape by hand. So for a polished diagram in a big document, or a wide BPMN model with swimlanes, the drawing tools look better. Visio is the one many large companies already use.
Sharing
- Sharing. Now sharing. A Mermaid diagram is just text, so you can paste it into a wiki page or a ticket. Tools such as GitHub and Notion turn that text into the diagram for you. A change is one edited line, such as E --> F, so anyone can see exactly what changed. draw.io is free and saves a file you can share or keep in a drive. Visio is paid, and the people reading the file usually need Visio too.
Pick one
- Pick the tool. Use Mermaid for quick maps that sit next to the requirements. Use draw.io for free, neat diagrams you place by hand. Use Visio when your company already has it and wants its files.
Recap
- The rules. Mermaid wins on speed and on sharing as text. draw.io wins on free, neat layouts. Visio wins when the company already uses it. Many analysts use more than one.
Mermaid, draw.io and Visio side by side
Price: Mermaid and draw.io are free; Visio is paid, through some Microsoft 365 plans or its own licence. Learning: Mermaid means learning a few lines of text; draw.io and Visio are drag and drop. Layout: Mermaid places the boxes for you; draw.io and Visio let you put every box exactly where you want. Formal notations: draw.io and Visio have BPMN and swimlane shapes; Mermaid only imitates them. Changes: a Mermaid diagram is text, so you can see exactly what changed between versions.
Using them together
You don't have to pick only one. Draft the flow quickly in Mermaid, then bring it into draw.io: in draw.io, go to Arrange, Insert, Mermaid (older versions have it under Arrange, Insert, Advanced) and paste the code. Tidy the layout by hand there. If the company needs a Visio file, draw.io can export the diagram as a .vsdx file that Visio opens. Check the result in Visio before you send it, because some styles can change on the way.
Working on a diagram with others
draw.io and Visio for the web let two people edit the same diagram at the same time, for example in Confluence, Google Drive or Microsoft 365. Mermaid works differently: the diagram lives as text in a document, ticket or code repository, and people review the change to the text. That suits teams that already review work that way, but a stakeholder who just wants to drag a box will find draw.io easier.
Common mistakes
- Brackets or special characters inside a label. A label like B[Check receipt (paper)] confuses Mermaid, because brackets mark shapes. Put the text in double quotes instead: B["Check receipt (paper)"].
- A typo in a node ID. IDs are case-sensitive, so typing e --> F instead of E --> F creates a new, empty box called e. Check that each arrow uses exactly the same ID as the shape it should join.
- Naming a box with the word end in lowercase. In a Mermaid flowchart, a node called end in lowercase breaks the diagram. Use a different ID, or write End or END.
- Trying to fix the layout by hand in Mermaid. Mermaid places every shape itself, so you can't drag a box into place. If the layout has to look a certain way for a document or sign-off pack, draw it in draw.io or Visio.
When a business analyst uses this
In a process workshop, a business analyst can type the refund flow in Mermaid while people talk, and change a step by editing one line. The text then goes on the GitHub or Notion page next to the requirements. If the final sign-off pack needs a polished map, the analyst redraws it in draw.io, or in Visio if the company uses it.
Questions people ask
Is Mermaid free to use?
Yes. Mermaid is open source, and the Mermaid live editor runs free in your browser, so you can write and preview a flowchart without installing anything.
Can GitHub show Mermaid diagrams?
Yes. Put the Mermaid text in a code block marked mermaid in a Markdown file, issue or pull request, and GitHub draws the diagram instead of showing the code.
Is draw.io free?
Yes. draw.io is free in the browser and as a desktop app. You can save your diagrams as files and keep them on your computer or in a drive.
