JavaScript to Flowchart Converter

Paste a JavaScript function or script and see its logic as a flowchart. Loops, conditions and early returns become clear paths, prompt() and console.log() become input/output boxes, and ▶ Explain steps through it with every variable shown.

  • Functions, early return and loops drawn as real paths
  • for, for…of, while and if / else as decisions
  • console.log and prompt as input/output boxes
  • Array operations as clear process steps
  • Animated dry run with a variable trace table
  • Export PNG, SVG, PDF, PowerPoint or Mermaid

How it works

  1. Paste your JavaScript and a sample input
  2. The AI draws the flowchart
  3. Press ▶ Explain to watch it run
  4. Export it or share a link

Try it with

  • for (let i = 1; i <= 15; i++) { if (i % 15 === 0) console.log("FizzBuzz") else if (i % 3 === 0) console.log("Fizz") else if (i % 5 === 0) console.log("Buzz") else console.log(i) }
  • const nums = [4, 9, 2, 7] let max = nums[0] for (const n of nums) { if (n > max) max = n } console.log("Max:", max)
  • function isValid(pw) { if (pw.length < 8) return false if (!/[0-9]/.test(pw)) return false if (!/[A-Z]/.test(pw)) return false return true } console.log(isValid("Secret123"))

Frequently asked questions

Is it free?

Yes. Drawing by hand is always free and every account includes free AI credits. AI Flowchart Pro adds unlimited AI generation and every diagram type.

Can it draw async code or callbacks?

It works best on synchronous logic: functions, loops and conditions. For calls between services (fetch, APIs, auth flows) a sequence diagram shows the order of messages more clearly, and the AI can draw that too.

How is an early return shown?

As an arrow from the decision straight to the end of the function, so every way out of the function is visible.

Does it run my JavaScript?

No. The AI reads the code and works out the dry run; nothing is executed.

Can I export it?

Yes — PNG, SVG, PDF, PowerPoint with an editable slide, Mermaid code and draw.io. You can also share a live link or present it full screen.

Ready-made examples, explained

All diagram templates →

Related tools

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