ThinBASIC is a BASIC programming language for Windows.
Developed by Eros Olmi and Petr Schreiber since 2004.

For beginner, for guru

We took the best from various BASIC implementations and added something ours. We don’t believe in semicolons.
We like easy to write, easy to read code.


Those who want may go hardcore by using advanced features such as direct memory manipulation, overlays or using inline assembly. Yes, in an interpreter. At native speed.

Best from both worlds

Interpreted nature of the language allows immediate execution of the scripts, without wait for compilation.
This allows faster iterations, brings more fun and less waiting.


Any script can be converted to EXE file you can further distribute to users without thinBasic installed.
No dependencies on .NET, Java or redistributables.

Modular and extensible

Core language is very simple yet very complete. The specific functionality for file system interactions, GUI and a lot more is provided via dedicated modules each extending thinBASIC language with new keywords.


ThinBASIC provides SDK allowing anyone to extend the language with compiled modules, bringing new features at top execution speed. Win32 and COM DLLs are also a go.

Keeping it simple

Everything you need for the development is present in the installer. The interpreter itself, development environment, help file and examples to get you started. All that in few megabytes.


We want you getting better, we want you to understand what we develop. That is why we provide the community and education under one roof of this website as well.

What do you get with thinBASIC?


ThinBASIC IDE (Integrated Development Environment).

Developed and maintained directly by thinBASIC authors, thinAir is the official script editor. Many easy-to-use features make thinBasic programmer’s day more productive.

It allows creating new scripts from templates, debugging and offers and complete document outline as well, for easier navigation between types and functions.

thinAir: thinBASIC IDE


ThinBASIC Debugger.

Unlike some other interpreters, thinBasic does support stepping through the code line by line in interactive mode, while allowing to skip directly to a user defined breakpoints.

It also allows variable inspection in multiple scopes, while providing detailed information even for more complex structures such as arrays or user defined types.



ThinBASIC pseudo compiler.

Any thinBasic script can be converted to EXE file, directly with this official tool. You can provide the EXE with the usual metadata, such as version information, custom icon and more.

This is the tool of choice when you need to ship your application to somebody without thinBasic installation. Just click a button and create an independent EXE file.