A free diagram maker that runs in your browser
Diagram Smith is a free online diagram maker: a set of 25 diagram and chart tools, one page for each kind of diagram. Every tool runs in your web browser with no sign-up. Pick the tool for the diagram you need, build it on screen and download the result as an image or a PDF.
There are three kinds of tool. The canvas tools (flowchart, data flow diagram, decision tree, concept map, network diagram, tree diagram) let you drag shapes and arrows around, and they can also turn typed text into a diagram and arrange the shapes for you. The text-to-diagram tools (UML class diagram, ER diagram, sequence diagram) draw the diagram as you type plain text. The chart tools (pie chart, line graph, gauge, Sankey diagram) redraw as you type or paste numbers from a spreadsheet.
- Open the tool that matches your diagram.
- Add shapes, or type or paste your content.
- Check the result. Your work is saved automatically in your browser.
- Download it as PNG, SVG or PDF. PNG comes in normal, 2x and 4x size (4x is print quality), and exports carry no watermark.
What you type is not uploaded, and the tools work on a phone as well as on a computer.
Which diagram should I use?
Use the diagram that matches what you need to show:
- Steps and decisions: a flowchart shows the steps of a process and its yes/no decisions. Start from a flowchart template if you want a ready-made layout.
- How data moves: a data flow diagram (DFD) shows how data moves between processes, data stores and outside people or systems.
- Choices with risk: a decision tree compares choices with probabilities and payoffs and works out the expected value of each branch.
- Numbers: a pie chart shows parts of a whole as percentages, a line graph shows a value changing over time, a gauge shows one value against its range, and a Sankey diagram shows how amounts flow from sources to destinations.
- Plans and people: a Gantt chart plans a project schedule with start and end dates, a timeline shows events in date order, an org chart shows who reports to whom, a RACI matrix shows who is Responsible, Accountable, Consulted and Informed for each task, and a SWOT chart lists strengths, weaknesses, opportunities and threats.
- Software and networks: a UML class diagram shows the classes of a program and how they relate, an ER diagram shows database tables and their keys, a sequence diagram shows messages passed between parts of a system over time, and a network diagram shows the devices and links of a computer network.
- Family and inheritance: a family tree shows ancestors and relatives, a family tree chart prints an ancestor chart of 2 to 6 generations, a genogram adds relationship types and conditions, and a pedigree chart tracks an inherited trait through generations.
- Ideas and groups: a Venn diagram shows what groups have in common (the 3 circle Venn diagram also works out unions and intersections), a concept map links ideas with labelled arrows, and a tree diagram shows a hierarchy or branching outcomes.