Data Flow Diagram Generator Data Flow Diagrams
Describe your system and our AI will create professional data flow diagrams with processes, data stores, and external entities. Perfect for system analysis, database design, and software documentation.
Data Flow Diagram Generator
Free to try ·
Your data flow diagram will appear here
Describe your system and click Generate
Data Flow Diagram Examples
Browse DFD examples or generate your own above
Level 0 Context Diagram
A Level 0 context diagram showing a central system process surrounded by external entities (customers, suppliers, administrators) with labeled data flows indicating information exchange between the system and its environment.
Online Shopping System DFD
A Level 1 DFD for an online shopping system decomposing the main process into order processing, payment handling, inventory management, and shipping fulfillment with data stores and external entities.
Library Management System DFD
A Level 1 DFD for a library management system with processes for book cataloging, lending and returns, member registration, and fine calculation, connected to data stores for books, members, and transactions.
Student Registration System DFD
A Level 1 DFD for a student registration system with processes for student enrollment, course scheduling, grade processing, and transcript generation, linked to student, course, and enrollment data stores.
Healthcare Patient Management DFD
A Level 1 DFD for a healthcare patient management system with processes for patient registration, appointment scheduling, diagnosis and treatment, and billing, connected to patient, medical records, and billing data stores.
Banking Transaction Processing DFD
A Level 2 DFD decomposing the banking transaction processing into detailed sub-processes: transaction validation, fraud detection, authorization, account update, and settlement, with corresponding data stores and external systems.
4 more examples available
Sign in for free to unlock all example diagrams and generate your own 4k custom diagrams.
What Is a Data Flow Diagram (DFD)?
A data flow diagram (DFD) is a graphical representation that shows how data moves through an information system. DFDs illustrate the processes that transform data, the data stores where information is held, the external entities that interact with the system, and the data flows that connect them all. Originally developed as part of structured systems analysis in the 1970s by Larry Constantine and Ed Yourdon, DFDs remain one of the most widely used tools in systems analysis and software engineering for understanding how a system receives, processes, stores, and outputs information.
DFD Levels: Context, Level 1, and Level 2
- Level 0 (Context Diagram): The highest level of abstraction showing the entire system as a single process with external entities and their data flows — provides a big-picture overview of system boundaries and interactions
- Level 1 DFD: Decomposes the single process from Level 0 into major sub-processes, showing data stores and the detailed data flows between processes, stores, and external entities
- Level 2 DFD: Further decomposes individual Level 1 processes into more detailed sub-processes, revealing the internal logic and data handling within each major function
- Higher Levels (3+): Continue decomposing complex processes as needed, though most systems are adequately documented at Level 2 — deeper levels risk over-complexity without added clarity
Standard DFD Symbols and Notation
- Process (Circle or Rounded Rectangle): Represents a function or activity that transforms input data into output data — labeled with a verb-noun phrase like "Process Order" or "Validate Payment"
- Data Store (Open-Ended Rectangle or Parallel Lines): Represents a repository of data at rest, such as a database, file, or table — labeled with a reference number and name like "D1 Customer Records"
- External Entity (Square or Rectangle): Represents a source or destination of data outside the system boundary — examples include users, other systems, or organizations
- Data Flow (Arrow): Represents the movement of data between processes, stores, and entities — always labeled with the name of the data being transferred, like "Order Details" or "Invoice"
When to Use Data Flow Diagrams
Data flow diagrams are most valuable during the requirements gathering and system analysis phases of software development, where they help analysts and stakeholders visualize how information flows through a proposed or existing system. DFDs are essential for database design, as they reveal what data needs to be stored and how it is accessed. They support process improvement initiatives by making inefficiencies and redundancies visible. DFDs are widely used in education for teaching systems analysis concepts. They are also valuable for security analysis, as tracking data flows helps identify where sensitive information is exposed and where access controls are needed.
Frequently Asked Questions
More Diagram Tools
DiagramsAI Flowchart Generator
Create professional flowcharts for business processes, workflows, and decision trees with AI assistance.
DiagramsER Diagram Generator
Generate entity-relationship diagrams for database design and data modeling with AI-powered visualization.
DiagramsBlock Diagram Generator
Create block diagrams for system overviews, signal processing, and engineering documentation.