Code to flowchart converter
Paste a function or some pseudocode. You get its control flow as a flowchart: inputs as parallelograms, conditions as diamonds, loops that point back where they belong.
Flowchart
Mermaid code for this chart
flowchart TD
n1(["Start"])
n2[/"Read n"/]
n3["Set total to 0 and i to 1"]
n4{"Is i less than or equal to n?"}
n5["Add i to total"]
n6["Add 1 to i"]
n7[/"Print total"/]
n8(["End"])
n1 --> n2
n2 --> n3
n3 --> n4
n4 -->|"yes"| n5
n5 --> n6
n4 -->|"no"| n7
n7 --> n8
n6 --> n4How code maps to flowchart shapes
Algorithm flowcharts follow the conventions in ISO 5807, the standard for program flowcharts. Once you know the mapping you can also draw them by hand in the flowchart maker.
Writing an algorithm flowchart for an exam
Examiners look for four things: one Start and one End, every input and output in a parallelogram, every condition in a diamond with labelled Yes/No arrows, and loops drawn as a diamond with an arrow going back up. Keep processing boxes short, like total ← total + i.
| In code | In the flowchart |
|---|---|
| Function begins / returns | Terminator (oval): Start, End |
input(), reading a file, parameters | Parallelogram (input) |
| Assignment, arithmetic | Rectangle (process) |
if / else if / switch | Diamond with labelled arrows |
for / while | Diamond + arrow back to it |
| Call to another function | Predefined process (double-sided box) |
print, return value | Parallelogram (output) |
| Database query | Cylinder |
Questions people ask
Which programming languages does it understand?
Any mainstream language: Python, JavaScript, TypeScript, Java, C, C++, C#, Go, PHP, Ruby and more, plus pseudocode written in plain English. The AI reads the control flow, not the syntax, so language doesn’t matter much.
How are loops drawn?
A for or while loop becomes a decision diamond (“Is i ≤ n?”) with a “yes” branch that does the loop body and an arrow back to the diamond, and a “no” branch that leaves the loop. That is the standard textbook way to draw a loop.
How long can the code be?
Up to 4,000 characters, roughly one or two functions. Flowcharts of whole programs are unreadable anyway; chart one function at a time and use a predefined-process box for calls to the others.
Can I convert pseudocode to a flowchart?
Yes. Pseudocode is often the easiest input because it’s already close to the wording of a flowchart. Keywords like IF, ELSE, WHILE, REPEAT UNTIL, INPUT and OUTPUT map straight to diamonds and parallelograms.
Is my code sent anywhere?
It’s sent to the AI model through Vercel AI Gateway to produce the chart and isn’t stored by FlowBuilder. Remove secrets such as API keys before pasting.