Flowchart Symbols and Their Meanings: The Complete Guide

Flowchart symbols are standardized shapes that represent different types of actions, decisions, and data in a process. Using the correct symbols makes your flowcharts immediately understandable to anyone familiar with the conventions. This guide covers every standard symbol, when to use it, and common mistakes to avoid.

The essential symbols

These five symbols handle 90% of flowcharting needs. Master these first.

Oval (Terminator)

╭─────────╮
│  Start  │
╰─────────╯

Purpose: Marks the beginning and end of a process.

When to use:

• Always use to show where the process starts
• Use to show each endpoint (there may be multiple end points)
• Label with "Start", "End", or a specific event like "Customer submits order"

Best practices:

• Every flowchart needs exactly one start terminator
• Use end terminators for each possible outcome
• Don't use ovals for intermediate steps

Rectangle (Process)

┌─────────────────┐
│  Process Step   │
└─────────────────┘

Purpose: Represents an action, task, or operation.

When to use:

• Any step where something happens
• Tasks that transform data or state
• Actions performed by people or systems

Examples:

• "Calculate total"
• "Send confirmation email"
• "Update inventory"
• "Review application"

Best practices:

• Use active verbs: "Process order" not "Order processing"
• Keep labels concise but specific
• One action per rectangle (don't combine multiple steps)

Diamond (Decision)

      ◇
     / \
   Yes   No

Purpose: Represents a question or condition that branches the flow.

When to use:

• Yes/No questions
• Condition checks
• Any point where the process can go multiple directions based on criteria

Examples:

• "Is payment valid?"
• "Order > $100?"
• "Approved?"
• "In stock?"

Best practices:

• Always phrase as a question with clear answers
• Label each outgoing branch (Yes/No, True/False, or specific values)
• Every branch must lead somewhere (no dead ends)

Arrow (Flow line)

───────────────>

Purpose: Shows the direction of flow from one step to the next.

When to use:

• Connect every shape to show sequence
• Always use arrows, not plain lines
• Point in the direction the process moves

Best practices:

• Flow primarily top-to-bottom or left-to-right
• Avoid crossing arrows when possible
• Use curved connectors if lines must cross

Parallelogram (Input/Output)

    ╱─────────────╲
   ╱  User Input   ╲
  ╱─────────────────╲

Purpose: Represents data entering or leaving the process.

When to use:

• User provides information (form submission, data entry)
• System reads from external source (file, database, API)
• Process outputs data (print, display, export)

Examples:

• "Enter customer details"
• "Read configuration file"
• "Display results"
• "Print report"

Secondary symbols

These symbols are less common but useful for specific situations.

Document

  ┌───────────────┐
  │   Document    │
  │               │
  └───────┐───────┘
          ╲_______╱

Purpose: Represents a document or report.

When to use:

• Physical or digital document is created
• Report is generated
• Document is referenced or used

Examples:

• "Generate invoice"
• "Print shipping label"
• "Review contract"

Multiple documents

  ┌───────────────┐
  │┌──────────────┐│
  ││   Reports    ││
  │└──────────────┘│
  └────────────────┘

Purpose: Represents multiple documents of the same type.

Examples:

• "Generate monthly reports"
• "Print batch invoices"

Predefined process (Subroutine)

  ┌─┬─────────────┬─┐
  │ │  Subroutine │ │
  └─┴─────────────┴─┘

Purpose: References another flowchart or documented process.

When to use:

• Linking to a separate detailed flowchart
• Referencing a standard procedure
• Avoiding repetition of common sub-processes

Examples:

• "Run payment processing"
• "Execute approval workflow"
• "Perform security check"

Database / Data store

    ╭───────────╮
   (│  Database │)
    ╰───────────╯

Purpose: Represents stored data (database, file system, data warehouse).

When to use:

• Reading from or writing to a database
• Storing or retrieving files
• Any persistent data storage

Examples:

• "Save to customer database"
• "Retrieve order history"
• "Update inventory records"

Manual operation

     ╲_____________╱
      ╲  Manual   ╱
       ╲_________╱

Purpose: An action performed manually rather than automatically.

When to use:

• Human intervention required
• Physical action needed
• Step that can't be automated

Examples:

• "Physically inspect package"
• "Sign document"
• "Insert components manually"

Preparation

  ╱─────────────────╲
 │    Initialize    │
  ╲_________________╱

Purpose: Setup or initialization step before main processing.

When to use:

• System initialization
• Variable setup
• Preparation before loop

Examples:

• "Initialize counter = 0"
• "Load configuration"
• "Set up connection"

On-page connector

    ◯
    A

Purpose: Connects parts of the flowchart on the same page.

When to use:

• Avoid long crossing lines
• Connect distant parts of a complex diagram
• Use matching labels (A to A, 1 to 1)

Off-page connector

    ⬠
    1

Purpose: Continues the flowchart on another page.

When to use:

• Flowchart spans multiple pages
• Link to continuation
• Label with page/section reference

Symbol usage by diagram type

Basic process flowchart

Uses: Terminator, Process, Decision, Arrow

Keep it simple. Most process documentation only needs these four symbols.

Data flow diagram

Uses: Process, Data store, Input/Output, Arrow

Focus on how data moves through the system rather than detailed steps.

System flowchart

Uses: All symbols including Database, Document, Multiple documents

Shows how data flows through a computer system including storage and reports.

Swimlane diagram

Uses: Any symbols, organized into lanes

Symbols are grouped by actor (person, department, system) in horizontal or vertical lanes.

Common mistakes and how to fix them

Using rectangles for everything

Problem: All steps are rectangles, including decisions and data operations.

Fix: Apply the right symbol for each type of step. Decisions become diamonds, data entry becomes parallelograms.

Unlabeled decision branches

Problem: Arrows leave a diamond but don't indicate which condition they represent.

Fix: Always label each branch coming from a decision. "Yes/No", "True/False", or the specific condition.

Dead ends

Problem: A branch leads nowhere—no terminator, no connection to another step.

Fix: Every path must eventually reach a terminator or loop back to the main flow.

Too many arrows crossing

Problem: The flowchart looks like spaghetti with lines crossing everywhere.

Fix: Reorganize layout. Use connectors for distant connections. Consider breaking into sub-processes.

Vague labels

Problem: "Process data", "Handle it", "Do stuff"—labels that don't explain what happens.

Fix: Be specific. "Validate email format", "Calculate shipping cost", "Send rejection email".

Missing start or end

Problem: The process just begins mid-flow or trails off without conclusion.

Fix: Always include a terminator at the start. Ensure all paths reach a terminator.

Inconsistent direction

Problem: Flow goes up, down, left, right unpredictably.

Fix: Maintain primary flow direction (top-to-bottom or left-to-right). Exceptions only for loops or returns.

Industry-specific symbols

Some industries have additional conventions:

Software development

• Loop/iteration symbol: Hexagon or special notation for repeating steps
• Parallel processing: Bar indicating concurrent activities
• API call: Sometimes shown with cloud shape

Manufacturing

• Delay: D-shaped symbol for wait times
• Inspection: Circle for quality checks
• Storage: Triangle pointing down for inventory/storage

Business process

• Timer: Clock symbol for scheduled events
• Message: Envelope for communications
• Gateway: Complex diamond patterns for multiple conditions

Creating flowcharts with correct symbols

Manual approach

1. Sketch the process on paper first
2. Identify each step type (action, decision, data)
3. Choose appropriate symbol for each
4. Draw in a diagramming tool using shape libraries
5. Verify symbols match the standard

AI-assisted approach

AI flowchart generators like Flowova automatically apply correct symbols based on your description:

• Describe "if customer is verified" → AI creates a diamond
• Describe "save to database" → AI uses database symbol
• Describe "print report" → AI uses document symbol

This removes the need to remember symbol meanings while creating—you focus on the process, and the AI handles the notation.

Quick reference table

Symbol	Name	Purpose
Oval	Terminator	Start and end points
Rectangle	Process	Action or task
Diamond	Decision	Yes/No branch point
Parallelogram	Input/Output	Data entering or leaving
Arrow	Flow line	Direction of flow
Rectangle with lines	Predefined process	Reference to sub-process
Cylinder	Database	Data storage
Wavy rectangle	Document	Document or report
Trapezoid	Manual operation	Human action required
Hexagon	Preparation	Setup or initialization
Circle	Connector	Link within page
Pentagon	Off-page	Link to another page

Summary

Flowchart symbols are a visual language. When everyone uses the same symbols consistently, flowcharts become immediately readable without explanation. Master the five essential symbols first (terminator, process, decision, input/output, arrow), then add secondary symbols as needed for specific use cases.

Don't let symbol choices slow you down. Start with the basics, create flowcharts that communicate clearly, and refine your symbol usage as you gain experience. The goal is communication, not perfection.

Related resources

• How to Make a Flowchart: Complete Beginner Guide – Step-by-step flowchart creation
• AI Flowchart Generator Guide – Using AI to create flowcharts
• Text to Flowchart Tool – Describe a process, get a flowchart
• Browse flowchart templates – Ready-to-use starting points