LogoLab

A free, web-based Logo programming environment for students. Learn programming through turtle graphics directly in your browser!

Try LogoLab Now

What is Logo?

Logo is an educational programming language designed in 1967 to teach programming concepts to beginners. It uses a "turtle" - a cursor that can be moved around the screen to draw shapes and patterns.

Features

• Full Logo interpreter with 50+ commands
• Turtle graphics with real-time rendering
• Procedures & variables - define your own commands
• Control structures - REPEAT, IF, FOR, WHILE
• Multiple turtles - create complex animations
• Lists support - advanced data manipulation
• Save & load - save your work locally
• Example programs - learn from built-in examples
• Command reference - in-app help
• Works offline - no server required
• Free forever - no sign-up, no ads

Quick Start

1. Visit the LogoLab website
2. Type some code in the editor, for example:

   REPEAT 4 [FD 100 RT 90]
   

3. Click Run (or press Ctrl+Enter)
4. Watch the turtle draw a square!

Example Programs

Draw a Star

REPEAT 5 [FD 100 RT 144]

Draw a Spiral

TO SPIRAL :size
  IF :size > 200 [STOP]
  FD :size
  RT 91
  SPIRAL :size + 2
END

SPIRAL 1

Draw a Flower

TO PETAL
  REPEAT 2 [
    REPEAT 30 [FD 3 RT 3]
    RT 90
  ]
END

REPEAT 12 [PETAL RT 30]

Command Reference

Movement

Command	Description
FORWARD n / FD n	Move forward n steps
BACK n / BK n	Move backward n steps
LEFT n / LT n	Turn left n degrees
RIGHT n / RT n	Turn right n degrees
HOME	Return to center
SETPOS [x y]	Move to position

Pen

Command	Description
PENUP / PU	Lift pen (stop drawing)
PENDOWN / PD	Lower pen (start drawing)
SETPENCOLOR color	Set pen color
SETPENSIZE n	Set pen width

Control

Command	Description
REPEAT n [...]	Repeat commands n times
IF cond [...]	Execute if condition is true
TO name ... END	Define a procedure

See the in-app Help button for the complete command reference.

Saving Your Work

• Auto-save: Your code is automatically saved to your browser
• Save button: Download your project as a .logo file
• Load button: Open a previously saved .logo file

Running Locally

1. Download or clone this repository
2. Open index.html in your browser
3. That's it! No build step required.

Support This Project

LogoLab is free and open source. If you find it useful, please consider:

• ☕ Buy me a coffee on Ko-fi
• ⭐ Star this repository
• 📢 Share with teachers and students

Attribution

This project is inspired by FMSLogo, a wonderful free implementation of Logo. We thank the FMSLogo team for keeping Logo alive for generations of students.

LogoLab is an independent web-based implementation and does not use any FMSLogo code.

License

MIT License - feel free to use, modify, and distribute.

---

Made with ❤️ for students everywhere.