Start / End
Also: terminator, terminal, oval
Where the process begins and ends. Label it "Start", "End", or the event that starts it, such as "Order received".
Flowchart symbols and what they mean
Most flowcharts need only five symbols: an oval to start and end, a rectangle for each step, a diamond for each question, a parallelogram for input and output, and arrows to connect them. The rest exist for special cases, mostly from the days of punched cards and tape.
The shapes are standardized in ISO 5807 (and the older ANSI X3.5), so a diamond means a decision in every tool and textbook.
Free. In draw.io, open the library with File › Open Library from › Device. Each symbol below also downloads as SVG, or copies straight into draw.io.
The basic five
These cover nearly every business process, algorithm or school assignment.
Process
Also: step, action, rectangle
One step: "Send invoice", "Check stock". Start the label with a verb.
Decision
Also: diamond, condition
A question with two or more answers, usually yes and no. Label every arrow that leaves it with its answer.
Input / Output
Also: data, parallelogram
Data going in or out: a customer fills in a form, the system prints a receipt.
Arrow
Also: flow line, connector line
Shows the order of the steps. Flow normally runs top to bottom or left to right.
Often used
Predefined process
Also: subroutine, subprocess
A step explained in detail elsewhere, such as in its own flowchart. The double side lines mark it.
Document
A step that produces or uses a document: a report, an invoice, a contract.
Multiple documents
Several documents, such as a batch of invoices.
Manual input
Someone types data in: a PIN, a search, a form field. The slanted top looks like a keyboard.
Manual operation
A step done by a person, not by a machine or system: "Sign the form", "Pack the box".
Preparation
Also: initialization, hexagon
A setup step before the main work, such as setting a counter to 0 before a loop.
Delay
Also: wait
Waiting: "Wait 24 hours", "Wait for approval".
Database
Also: direct access storage, cylinder
Data saved to or read from a database or disk.
Display
Information shown on a screen to a user.
On-page connector
A small circle with a letter. The flow jumps to the circle with the same letter, instead of drawing a long arrow across the page.
Off-page connector
The flow continues on another page. Write the page number and a letter inside.
Comment
Also: annotation
A note that explains a step, attached with a dashed line.
Rarely needed
You will meet these in older textbooks and data-processing charts. Most modern flowcharts get by without them.
Stored data
Data stored somewhere, without saying where.
Internal storage
Data held in memory while a program runs.
Loop limit
Marks the start and end of a loop. The two shapes share a label, such as "Each order".
Merge
Several sets of items combined into one.
Extract
Also: measurement
Taking part of a set out, for example pulling the overdue invoices from a list.
Sort
Putting items in order.
Collate
Arranging items into a set order or format.
Summing junction
Several flows join, and all of them must arrive before the process goes on (logical AND).
Or
Several flows join, and any one of them is enough to go on (logical OR).
Rules that keep a flowchart readable
One start, at the top. Flow goes down or to the right; arrows that go back up are loops, so keep them few.
One action per box, starting with a verb. If a box needs two lines of text, it is probably two steps.
Every decision has a labelled arrow for each answer. A diamond with an unlabelled arrow is the most common mistake.
If the chart no longer fits on a page, move a part into its own chart and show it as a predefined process.
Sketched a flowchart on paper or a whiteboard?
Take a photo. Sketch2scheme turns it into a clean, editable flowchart with these shapes, ready for draw.io, PNG or SVG.
Questions
What are the basic flowchart symbols?
The oval (start and end), the rectangle (a step), the diamond (a decision), the parallelogram (input or output) and the arrow. With these five you can draw almost any process.
What does a diamond mean in a flowchart?
A decision: a question such as "Is the payment approved?". Each arrow leaving the diamond is one answer and should be labelled, usually Yes and No.
What is the difference between a process and a predefined process?
A process is one step shown in full. A predefined process (the box with double side lines) stands for a whole set of steps described in another flowchart.
Is there an official standard for flowchart symbols?
Yes: ISO 5807, and the older ANSI X3.5. Most drawing tools, draw.io included, follow them.
More symbol charts
Symbols are drawn with draw.io (diagrams.net), which is open source. Use them freely in your own drawings, documents and lessons.