AI Code Flow Visualizer
See how your code executes with clear flow breakdowns
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How many ways can execution leave the function you are looking at? Three returns, an exception, and a break you forgot about? Can you list them without scrolling?
Control flow is the part of code that resists reading, because it is a shape and text is a line. The AI Code Flow Visualizer turns that shape into something you can see at once: the branches, the loops, the exits and the paths nothing ever takes.
Short answer: The AI Code Flow Visualizer is a free AIToolsay tool that maps the control flow of code. Paste a function or a file and it describes the branches, loops, conditions and exit points as a structured flow you can follow, along with the paths that are hard to reach.
What is AI Code Flow Visualizer?
The output is a map of how execution moves, produced as structured text you can read, copy into a document or turn into a diagram yourself.
The prompt box asks you to paste the code you want explained. For flow work, paste whole functions. A fragment produces a map with edges leading nowhere, because the branch you cut off was part of the shape.
What you get back is the decision structure: which condition leads where, which loops can exit early, and how many distinct paths run from entry to exit.
Why Use AI Code Flow Visualizer?
Counting paths is what tells you how much testing a function actually needs. Four independent conditions is sixteen combinations, and nobody notices that while writing the fourth one.
The second reason is finding paths nothing reaches. A branch that cannot be true, a catch that cannot fire, an else after a condition that already returned. These are invisible when reading top to bottom and obvious once the flow is laid out.
| What a flow map shows | Why it is hard to see in code |
|---|---|
| Number of distinct paths | Conditions are written separately and combine invisibly |
| Unreachable branches | The condition that excludes them is elsewhere |
| Early exits | Returns are scattered through the body |
| Loops with several exit conditions | Break, return and the loop condition all compete |
Who Should Use It?
- Developers writing tests who need to know how many paths exist before deciding on coverage
- Reviewers facing a function with deep nesting and several exits
- Anyone refactoring a long conditional and needing to preserve behaviour exactly
- People documenting business rules that only exist as nested conditions
- Learners meeting recursion, generators or early returns for the first time
Note Ask for the paths to be listed as well as the structure. A list of end to end paths is directly usable as a test plan, and it is the part most people forget to request.
How Does AI Code Flow Visualizer Work?
- Prompt box. Open the AI Code Flow Visualizer and paste whole functions, not fragments.
- Model selector. Choose the engine from MSB AI, OpenAI ChatGPT, Google Gemini, Anthropic Claude AI, xAI Grok AI, DeepSeek, Qwen, Meta AI, NVIDIA AI, OpenRouter AI and MiniMax.
- Advanced options accordion. There are ten controls in there: Language, Explanation Depth, Audience and Output Format as dropdowns, four toggles, a Depth slider and a free text field.
- Generate button. Code, model and settings run through the prompt engineering layer written for code explanation, which is the instruction set that produces a structural map rather than prose.
- Output card. The flow map appears under the button with a live word count, plus copy, listen, reuse, download and open in full view.
- Export row. DOC, TXT and HTML. TXT keeps the indentation of a text based flow map intact.
- Activity history. Session generations stay listed, which is how the flow before a refactor and the flow after it stay comparable.
Best Use Cases
- A function with nested conditions where the combinations are hard to hold
- Planning test coverage, using the path list as the plan
- Refactoring a long conditional while preserving behaviour
- Finding branches that nothing can reach
- Turning implicit business rules into something a non developer can review
- Comparing the flow before and after a change
Paths counted
The number of distinct routes from entry to exit, which is the number your test suite has to cover.
Unreachable branches
Conditions excluded by something earlier, which read perfectly well and can never run.
Every exit found
Returns, breaks and thrown errors collected together instead of scattered through the body.
Text you can keep
A map that fits in a pull request comment, rather than a picture that lives somewhere else.
| Why you are mapping it | Output Format | What to ask for |
|---|---|---|
| Planning tests | Step by Step | Every path as a numbered list |
| Reviewing a change | Summary | The path count before and after |
| Explaining a business rule | Plain Explanation | Conditions in plain words, no code terms |
| Hunting dead branches | Step by Step | Paths marked as unreachable |
Advanced Options Guide
| Option | What it controls | When to change it | Suggested start |
|---|---|---|---|
| Language | Auto Detect, Python, JavaScript, TypeScript, Java, C#, C++, Go, PHP or Ruby | Set it, because control flow constructs differ, especially around async and generators | Your language |
| Explanation Depth | High Level, Line by Line, Conceptual, Detailed, Beginner or Expert | Detailed keeps every branch, High Level collapses the small ones | Detailed |
| Audience | Beginner, Intermediate, Advanced, Non Technical, Team or Reviewer | Non Technical when the flow encodes a business rule someone else must approve | Team |
| Output Format | Plain Explanation, Inline Comments, Step by Step, Summary or Doc Comment | Step by Step gives the clearest text map of a flow | Step by Step |
| Line by Line | Adds statement level detail to the map | Turn off. It reintroduces the noise the map exists to remove | Off |
| Add Examples | Traces sample inputs along specific paths | Leave on. One traced input per path is what makes a map concrete | On |
| Add Summary | States the number of paths and exits up front | Keep on. The path count is the headline number | On |
| Note Edge Cases | Flags unreachable branches and paths with no test | Leave on. Unreachable code is the most valuable finding here | On |
| Depth | Slider from 1 to 100 controlling how far nested calls are followed | Raise it when the flow continues into helper functions you also pasted | 60 |
| Custom Instructions | Free text up to 1000 characters over the settings | Ask for the output shape you want | "List every path from entry to exit as a numbered test plan" |
Caution The map covers the code you pasted. If a called function can throw or return early, that is another exit and it will not appear unless you paste the callee too. Flow maps that stop at the function boundary are honest, not complete.
Example Inputs
def can_refund(order, user, now):
if order.status == "cancelled":
return False
if order.paid_at is None:
return False
if user.is_admin:
return True
if (now - order.paid_at).days > 30:
return False
if order.has_shipped and not order.is_returned:
return False
return TrueSix conditions and two possible answers. This is exactly the shape that looks trivial and is not: the admin branch short circuits three later rules, and whether that is intended is a question nobody has asked out loud.
Example Outputs
PATHS: 6 to False, 2 to True
entry
-> status == cancelled -> False [path 1]
-> paid_at is None -> False [path 2]
-> user.is_admin -> True [path 3]
-> more than 30 days since paid -> False [path 4]
-> shipped and not returned -> False [path 5]
-> otherwise -> True [path 6]
NOTE
Path 3 bypasses the 30 day rule and the shipping rule. An
admin can refund a shipped order from last year.The note at the bottom is the finding. Nothing in the code is wrong, and the flow map makes a policy decision visible that was never actually decided. That is what this tool is for.
When the flow spans several classes rather than one function, the AI UML Diagram Generator works at the right level, and for a whole system the AI Architecture Explainer is the better starting point.
Tips & Common Mistakes
What makes a good flow map
- Whole functions pasted, including every return
- A request for the paths listed as well as the structure
- Note Edge Cases left on so unreachable branches surface
- The map compared against your test suite
What produces a map you cannot use
- Pasting a fragment, so branches lead nowhere
- Leaving Line by Line on, which buries the shape
- Mapping several unrelated functions at once
- Assuming exits inside called functions are included
- ✅ Whole function pasted with all its returns
- ✅ Paths requested as a numbered list
- ✅ Note Edge Cases on
- ✅ Path count compared against the number of tests
- ✅ Any surprising short circuit raised with whoever owns the rule
Pro tip Generate the flow map before a refactor and again after it, then compare the path lists. If the number of paths or their outcomes changed, you altered behaviour, whatever the tests say. It is the cheapest behaviour preservation check available.
AIToolsay is a free AI tools platform built as a set of dedicated workspaces rather than one general chat box with many names attached. Each tool has its own prompt engineering and its own options panel, which is why an explanation tool asks about depth and audience rather than tone and length. All of the tools are free, and none of them asks you to create an account. Which engine answers is your call, from MSB AI, OpenAI ChatGPT, Google Gemini, Anthropic Claude AI, xAI Grok AI, DeepSeek, Qwen, Meta AI, NVIDIA AI, OpenRouter AI and MiniMax. Beyond the tool suite there is an AI directory, an AI models directory, courses, prompts, guides and news, all reachable from the AIToolsay homepage.
Frequently Asked Questions
Is the AI Code Flow Visualizer free?
Yes. It is free to use, nothing is installed, and no account is needed to map a function.
Does it produce a picture?
It produces a structured text map of the flow, which you can read directly, keep in a document or hand to a diagram tool. Text has the advantage that it fits in a pull request.
Can I use the output as a test plan?
Yes, and it is the best use. Ask for every path from entry to exit as a numbered list, then check each one against your test suite. Missing tests become obvious immediately.
Will it find unreachable code?
Often, with Note Edge Cases on. Branches excluded by an earlier condition are one of the clearest things a flow map exposes and one of the hardest to see while reading.
Does it follow calls into other functions?
Only if you paste them and raise Depth. Otherwise the map stops at the call, which means an exception thrown inside a callee will not appear as an exit.
Is it useful for async code?
Yes, and it is worth setting Language explicitly. Async control flow has exits that do not look like exits, and the language matters more than usual for reading them correctly.
How large a function can it handle?
One function at a time, of any reasonable size. If the map is too large to read, that is a finding about the function rather than a limitation of the tool.
The shape of a function is the part that decides how many things can go wrong in it. Paste the whole thing, ask for the paths as a list, and let the AI Code Flow Visualizer show you the branch nobody has thought about since the day it was written.
Thanks for reading, and enjoy the path count. If this changes how you plan your tests, join the AIToolsay community, follow along on social media, turn on push notifications for new tools, and subscribe to the newsletter for the occasional summary.
Let AI Speak.
Sabir
Founder of AIToolsay and a passionate AI enthusiast dedicated to building practical, user-friendly AI tools that simplify everyday tasks.
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