VisuAlg: learn algorithms by watching them run

VisuAlg is the free Portugol interpreter used in programming logic classes across Brazil and beyond. Write pseudocode in Portuguese, press run, and see every variable change line by line. Download VisuAlg here and start with our step-by-step guides.

Free to useWindows 7 to 11Linux via Wine
Laptop on a desk running VisuAlg with an average-grade algorithm, variables panel and output console
Simple. Visual. Beginner friendly.

What is VisuAlg?

VisuAlg is a free learning tool for writing and running algorithms in Portugol. It helps beginners understand programming logic by showing code, output and variable changes as the program runs.

Made for beginners

Learn variables, conditions, loops and functions without dealing with a complex setup.

See logic in action

Follow execution line by line and watch values change while your algorithm runs.

Skills that transfer

The same core ideas carry into languages such as Python, C, Java and Pascal.

Features that make VisuAlg a teaching favourite

A small program with a clear focus: show beginners exactly how an algorithm behaves.

Visual execution

Watch every variable change in the memory panel while the program runs, the feature that gives VisuAlg its name.

Portuguese commands

Write se, entao, para and enquanto instead of English keywords, so the logic of an algorithm is never hidden behind vocabulary.

Step by step and breakpoints

Run one line at a time with F8 or pause on any line with a breakpoint. Bugs become something you can see, not guess.

Lightweight and portable

The whole program fits in a few megabytes and runs from a folder, even from a USB stick on a shared lab computer.

Pascal export

Turn a finished algorithm into Pascal source code, a natural bridge from pseudocode to a compiled language.

Skins and teacher settings

Choose from several visual themes and add the course name, teacher and school to printouts and headers.

Random input generation

Fill leia commands with random values using aleatorio, so you can test an algorithm dozens of times without typing.

Plain text files

Algorithms save as simple .alg text files that open in any editor and are easy to share, submit or version.

Download VisuAlg 3.0

One click starts the download of the latest VisuAlg package published by its author. No sign-up and no installer bundles.

VisuAlg 3.0 for Windows
Version 3.0.7Windows 7, 8, 10, 11License: freeSource: GitHub
Download VisuAlg 3.0

After downloading, extract the package to a folder such as C:\VISUALG3 and run the executable. Need help? Follow the installation steps below.

How to install VisuAlg on Windows

There is no complex installer. You download, extract and run. The whole process takes less than five minutes.

  1. Download the package

    Press the download button above. The file comes from the project's public release page, so it is the author's original build.

  2. Extract to a folder

    Unzip it to a permanent location such as C:\VISUALG3. Do not run it from inside the ZIP, or your settings will not be saved.

  3. Launch the program

    Double-click the executable. If Windows SmartScreen appears, choose More info and then Run anyway.

  4. Fix skins if needed

    If themes do not change, copy the Skins sub-folder to C:\Skins as the author recommends, then restart.

  5. Run a test algorithm

    Type a short program, press F9 and check that the console prints your message. You are ready to learn.

Want screenshots and troubleshooting? Read the full VisuAlg installation guide.

Your first algorithm in VisuAlg

This program reads two grades, calculates the average and tells the student whether they passed. It uses almost every basic idea at once: declaration, input, assignment, a calculation, a decision and formatted output.

Notice the structure. The name comes after algoritmo, variables are declared under var, and commands live between inicio and fimalgoritmo. The arrow <- means "receives", and media:4:2 prints the average with two decimal places.

Paste it into the editor and press F9. Then press F8 to run it again one line at a time and watch MEDIA appear in the variables panel the moment line ten executes.

More beginner examples

algoritmo "media_notas"
// Calcula a media de duas notas
var
   n1, n2, media: real
inicio
   escreva("Primeira nota: ")
   leia(n1)
   escreva("Segunda nota: ")
   leia(n2)
   media <- (n1 + n2) / 2
   se media >= 7 entao
      escreval("Aprovado com media ", media:4:2)
   senao
      escreval("Recuperacao, media ", media:4:2)
   fimse
fimalgoritmo

VisuAlg syntax quick reference

The commands you will use in almost every exercise. VisuAlg is not case-sensitive, so ESCREVA and escreva work the same way.

CommandWhat it does
algoritmo "nome"Starts the program and gives it a name
varOpens the variable declaration section
inicio / fimalgoritmoMarks the start and end of the main commands
x <- 10Assigns a value to a variable
escreva() / escreval()Prints output, without or with a line break
leia()Reads a value typed by the user
se ... entao ... senao ... fimseMakes a decision
escolha ... caso ... fimescolhaChooses between many fixed values
para i de 1 ate n faca ... fimparaRepeats a fixed number of times
enquanto ... faca ... fimenquantoRepeats while a condition is true
repita ... ateRepeats until a condition becomes true
vetor[1..10] de inteiroDeclares an array
funcao / procedimentoDeclares reusable subprograms
\   %   ^Integer division, remainder and power
e   ou   naoLogical and, or, not

The four data types are inteiro, real, caractere and logico. Learn how each behaves in the variables and data types guide.

VisuAlg compared with other learning tools

Several tools teach programming logic in Portuguese. Each has strengths, and many courses use more than one.

CriteriaVisuAlgPortugol StudioPython
Commands in PortugueseYesYesNo
Live variables panelBuilt inInspectorNeeds a debugger
Download sizeA few MBLarger, needs JavaModerate
Runs natively on Linux and MacVia WineYesYes
Used in professional workNo, teaching onlyNo, teaching onlyYes

Choose VisuAlg when your course follows its Pascal-like Portugol dialect or when you want the lightest possible setup. Move to a real language once loops, arrays and functions feel natural.

System requirements

VisuAlg runs on almost any Windows computer made in the last fifteen years.

Operating system
Windows 7 to 11
Disk space
About 10 MB
Memory
512 MB or more
Best resolution
1366 × 768

On Linux, VisuAlg runs through Wine. On macOS, use a Wine-based tool or a Windows virtual machine. Our Linux and Mac guide covers both.

Tips for learning faster with VisuAlg

Small habits that save hours of frustration, collected from students and teachers who use VisuAlg every semester.

For students

Plan before you type. Write the steps in plain words or draw a quick flowchart, then translate each step into a VisuAlg command. Most errors come from unclear thinking, not from syntax.

Run often. Press F9 after every few lines instead of writing the whole program first. When something breaks, you will know it was the last thing you added.

Use step-by-step mode on purpose. Before pressing F8, predict the next value of each variable. Comparing your prediction with the variables panel is the fastest way to build real intuition about loops and conditions.

Keep a folder of solved exercises. Every .alg file is a reusable pattern: counters, accumulators, finding the largest value, validating input.

For teachers

Project the program and use timed execution so the whole class sees each line run at a readable speed. It turns abstract ideas like scope and loop counters into something visible.

Set the course, teacher and school names in the settings so printed algorithms carry the right header for assignments.

Encourage students to export finished algorithms to Pascal. Seeing the same logic in a compiled language shows them that pseudocode is a real step toward professional programming, not a detour.

Because VisuAlg runs from a folder, you can place it on a shared drive or USB stick and have a whole lab ready in minutes.

VisuAlg guides

Short, practical tutorials that take you from installation to functions, with code you can paste and run.

Frequently asked questions

Quick answers to common questions about downloading, running and learning with VisuAlg.

What is VisuAlg?

VisuAlg is a free Windows program that lets you write, run and debug algorithms in Portugol, a pseudocode based on Portuguese. It shows variables changing in real time, which makes it a popular first tool in programming logic courses.

Is VisuAlg free to download?

Yes. VisuAlg 3.0 is distributed free of charge by its author through its public project page. The download button on this site links straight to that package, so you never pay and never need an account.

Which version of VisuAlg should I use?

Use VisuAlg 3.0, the latest major release. It added skins, accepts correctly accented Portuguese commands such as PARA ... FAÇA, and keeps compatibility with algorithms written for version 2.5.

Does VisuAlg work on Windows 11?

Yes. VisuAlg runs on Windows 7, 8, 10 and 11. If SmartScreen shows a warning on the first launch, choose More info and then Run anyway, because the program is not digitally signed.

Can I use VisuAlg on Mac or Linux?

Not natively, but it runs on Linux through Wine, and on macOS through Wine-based tools or a Windows virtual machine. Browser-based re-implementations of the VisuAlg dialect are another option.

What language does VisuAlg use?

It uses Portugol, also called Portuguese structured pseudocode. Commands such as escreva, leia, se, entao and para read like Portuguese, so beginners focus on logic instead of English keywords.

Is VisuAlg a real programming language?

Not exactly. Portugol is a teaching pseudo-language, and VisuAlg is its interpreter. The skills you learn, such as variables, conditions, loops and functions, transfer directly to Pascal, C, Python and Java.

How do I run an algorithm in VisuAlg?

Write the code in the editor and press F9 to run it. Press F8 to run one line at a time, and F5 to set a breakpoint. Output appears in a console window and variables show in a side panel.

Why does VisuAlg say a variable was not found?

Every variable must be declared in the var section before inicio. Check the spelling, remove accented letters from names, and make sure the declaration has a valid type such as inteiro or real.

Is this the official VisuAlg website?

No. visualg.org is an independent learning resource. VisuAlg is created and maintained by its original authors, and our download link points to the project's public distribution page.