Draw data flow diagrams in minutes, not hours
DFD Maker is built only for data flow diagrams. Drag in entities, processes and data stores, connect them, and check your DFD against the rules before you submit it. It's free, and there's nothing to install.
- No sign-up
- No watermark
- PNG & SVG export
- Auto-saves in your browser
Everything you need for a correct DFD
General diagram tools make you hunt for the right shapes and never tell you when a DFD is wrong. DFD Maker is built around how DFDs actually work.
Real DFD symbols
External entities, processes, data stores and data flows, plus multi-process, control process, duplicates and boundaries.
DFD rule checker
One click finds black holes, miracles, entity-to-entity flows, unused data stores and unnamed flows before your teacher does.
Smart data flows
Drag from a shape to connect. Choose straight, curved, S-curve or elbow lines, flip or bend them, and make two-way flows.
Auto numbering
Processes are numbered 1.0, 2.0, 3.0 and data stores D1, D2, D3 automatically, so your levels stay consistent.
Themes & styling
Colourful, black & white for printing, pastel or blueprint. Change fonts, text size, colours and line widths.
Export anywhere
Export PNG, JPEG, WebP, SVG, PDF or HTML, with transparent backgrounds. Open and save draw.io XML files too.
Make a DFD in 3 steps
Most students finish a context diagram in under five minutes.
Add your shapes
Drag external entities, processes and data stores onto the canvas, or press E, P or D. Double-click any shape to name it.
Connect the data flows
Hover a shape and drag from a blue dot to another shape. Type what data moves along the arrow, like “Order details”.
Check & download
Click Check DFD rules to fix mistakes, then download your diagram as PNG or SVG. Your work auto-saves as you go.
DFD symbols explained
Every data flow diagram uses four building blocks. DFD Maker supports both common notations and can switch between them with one click. Read the full symbols guide →
External entity
Rectangle (both notations)A person, organisation or outside system that sends data in or receives data out, e.g. Customer, Bank.
Process
Circle (Yourdon) · Rounded box (Gane–Sarson)Work that changes data. Name it with a verb and a noun: Validate order, Generate bill.
Data store
Open-ended box · D1, D2…Where data rests: a database table, file or register, e.g. D1 Orders, D2 Customers.
Data flow
Labelled arrowData moving between parts of the system. Always name it with the data it carries, like Payment details.
Context diagram, Level 1 & Level 2
DFDs are drawn in levels. Each level zooms into the one above it. Start with a ready-made example and edit it. Learn about DFD levels →
Context diagram (Level 0)
The whole system as a single process “0”, with every external entity around it. It shows the system's boundary and what goes in and out.
Open context diagram example →Level 1 DFD
Breaks process 0 into its main sub-processes (1.0, 2.0, 3.0…) and adds the data stores they read from and write to.
Open Level 1 example →Level 2 DFD
Zooms into one Level 1 process and shows its detailed steps, numbered 1.1, 1.2, 1.3. Use a system boundary to frame it.
Start a Level 2 DFD →Catch DFD mistakes before you submit
These are the mistakes examiners and project guides mark down most often. DFD Maker checks for all of them with one click.
- ✕Black hole: a process that takes input but produces no output.
- ✕Miracle: a process that produces output from no input.
- ✕Entity to entity: data flowing directly between two external entities without a process.
- ✕Entity to store: an external entity reading or writing a data store directly.
- ✕Unnamed flows: arrows with no label.
A DFD tool, not a general drawing app
General diagram apps can draw a DFD, but they don't know what a DFD is.
| DFD Maker | General diagram apps | |
|---|---|---|
| DFD symbols ready to use | ✅ Both notations | Search through shape libraries |
| Checks DFD rules | ✅ Built in | ❌ |
| Automatic process & store numbers | ✅ | ❌ Type them by hand |
| Switch Yourdon ↔ Gane–Sarson | ✅ One click | ❌ Redraw every shape |
| Sign-up needed | ✅ Never | Often |
| Price | ✅ Free | Free to paid |
Frequently asked questions
Quick answers about DFD Maker and data flow diagrams. See all questions →
Is DFD Maker free?
Yes, completely. There's no sign-up, no watermark on downloads and no limit on how many diagrams you make.
What is a data flow diagram (DFD)?
A data flow diagram shows how data moves through a system: where it comes from (external entities), what changes it (processes), where it's kept (data stores) and how it travels between them (data flows). DFDs are widely used in software engineering, system analysis and BCA, MCA and B.Tech projects.
What is the difference between a context diagram and a Level 1 DFD?
A context diagram, also called a Level 0 DFD, shows the entire system as one process connected to its external entities. A Level 1 DFD opens that single process up into its main sub-processes (1.0, 2.0, 3.0…) and shows the data stores they use.
Which notation should I use: Yourdon–DeMarco or Gane–Sarson?
Use whichever your syllabus or teacher uses. Yourdon–DeMarco draws processes as circles, and Gane–Sarson draws them as rounded rectangles with a number strip. In DFD Maker you can switch at any time and the whole diagram is redrawn.
Where are my diagrams saved?
Your diagram saves automatically in your own browser, so nothing is uploaded to any server. To keep a copy or move it to another computer, click Save to download a diagram file, and use Import to load it again.
Can I download my DFD as an image?
Yes. Download a high-resolution PNG to paste into Word, Google Docs or PowerPoint, or an SVG that stays sharp at any size. You can also right-click a selection and copy it as an image.
Does it work on phones and tablets?
Yes, every feature works on phones and tablets. Use the bar at the bottom: Shapes opens the shape library, Style opens colours and text settings, and More has notation, line style and the DFD rule checker. Tap a shape to select it, drag one of its dots to draw a flow, double-tap to rename, long-press for more options and pinch to zoom.
What is the difference between a DFD and a flowchart?
A flowchart shows the order of steps and decisions in a process (control flow). A DFD shows how data moves between processes, stores and outside entities. It has no decisions or loops.
Ready to draw your DFD?
Open the editor and have your context diagram ready in minutes.