Language Model Builder
Free, educational macOS application to build and train local LLMs.
Quick Keypoints
- Completely free desktop educational application with no accounts or subscriptions.
- Pairs a theoretical interactive textbook with a practical model training dashboard.
- Enables users to train tokenizers, load custom text datasets, and fine-tune weights.
- Runs entirely locally on macOS utilizing Apple's native MLX framework for privacy.
What is Language Model Builder?
Language Model Builder (languagemodelbuilder.com) is a free educational desktop application built for macOS that teaches users how large language models are constructed. Powered by Apple's MLX framework, it lets developers train tokenizers, load training datasets, pre-train and fine-tune models entirely on-device.
Language Model Builder is a learning workbench for local AI engineering. By guiding users through the components of tokenizer construction, dataset mapping, and neural network training, it demystifies LLM internal architectures. Training runs locally on Apple Silicon, providing hands-on experience without API dependencies.
Who Needs Language Model Builder?
Computer science students, AI enthusiasts, and software engineers wanting to learn LLM mechanics from first principles.
Primary Use Cases
- Autocompleting code syntax and logic blocks in real-time.
- Explaining complex functions and debugging codebase errors.
- Generating boilerplate code and unit test suites automatically.
Important Features
- Interactive Textbook: Integrates model theory reading directly with training consoles.
- Tokenizer Builder: Train custom tokenizers on target text files to inspect segment tokens.
- MLX Training: High-efficiency local model training optimized for Mac GPU and CPU structures.
- Local Chat Console: Instantly chat with your trained model once training cycles finish.
Current Updates About Language Model Builder
- Released in July 2026 by Felix Rieseberg, featuring MLX-powered pre-training, fine-tuning (SFT), alignment (DPO), and an interactive textbook.
- Current Version: v1.0
Pricing Plans
| Plan | Price |
|---|---|
| Standalone AppCompletely free educational desktop app for Apple Silicon Macs to train models from scratch locally. | Free |