companies

Unsloth AI

Open-source library for fast, memory-efficient fine-tuning of open-weight LLMs on consumer and single GPUs.

Unsloth AI was founded in 2023 by brothers Daniel Han and Michael Han, who built the project after Daniel's work at NVIDIA optimizing algorithms like t-SNE and later hunting down bugs in open-weight models such as Gemma, Llama, and Phi. The company went through Y Combinator and has stayed a lean, engineering-heavy team focused almost entirely on making fine-tuning faster and cheaper rather than building a broad platform. Unsloth's core product is an open-source Python library that rewrites the training kernels used for LoRA and QLoRA fine-tuning, cutting VRAM usage enough to fine-tune a 7-billion-parameter model on a single 24GB consumer GPU. It supports hundreds of open-weight model families and ships free notebooks for Google Colab and Kaggle so anyone can fine-tune without paying for compute beyond what those platforms already provide. Paid Pro and Enterprise tiers add faster training plus multi-GPU and multi-node support for teams that outgrow a single card. The library has become a default reference point in open-source LLM communities on Reddit and Hugging Face, with millions of monthly downloads and thousands of community-trained models built on top of it.

Founded

2023

Headquarters

San Francisco, United States

Sector

infrastructure