⚡ LitGPT

20+ high-performance LLMs with recipes to pretrain, finetune, and deploy at scale.

✅ From scratch implementations      ✅ No abstractions         ✅ Beginner friendly
   ✅ Flash attention                   ✅ FSDP                    ✅ LoRA, QLoRA, Adapter
✅ Reduce GPU memory (fp4/8/16/32)   ✅ 1-1000+ GPUs/TPUs       ✅ 20+ LLMs         

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Quick start • Models • Finetune • Deploy • All workflows • Features • Recipes (YAML) • Lightning AI • Tutorials

 

 

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• Notebooks: Persistent GPU workspaces where AI helps you code and analyze.
• Inference: Deploy models as inference APIs.

Finetune, pretrain, and inference LLMs Lightning fast ⚡⚡

Every LLM is implemented from scratch with no abstractions and full control, making them blazing fast, minimal, and performant at enterprise scale.

✅ Enterprise ready - Apache 2.0 for unlimited enterprise use.
✅ Developer friendly - Easy debugging with no abstraction layers and single file implementations.
✅ Optimized performance - Models designed to maximize performance, reduce costs, and speed up training.
✅ Proven recipes - Highly-optimized training/finetuning recipes tested at enterprise scale.

Quick start

Install LitGPT

pip install 'litgpt[extra]'

Load and use any of the 20+ LLMs:

from litgpt import LLM

llm = LLM.load("microsoft/phi-2")
text = llm.generate("Fix the spelling: Every fall, the family goes to the mountains.")
print(text)
# Corrected Sentence: Every fall, the family goes to the mountains.

✅ Optimized for fast inference
✅ Quantization
✅ Runs on low-memory GPUs
✅ No layers of internal abstractions
✅ Optimized for production scale

git clone https://github.com/Lightning-AI/litgpt
cd litgpt
# if using uv
uv sync --all-extras
# if using pip
pip install -e ".[extra,compiler,test]"

Explore the full Python API docs.

Choose from 20+ LLMs

Every model is written from scratch to maximize performance and remove layers of abstraction: