OpenChat (8,984 Stars) 2026: The Open-Source Chatbot Model Family You Can Fine-Tune and Run Locally

OpenChat (8,984 stars) is an open-source family of chatbot models known for strong performance with mixed data training. Here is how to run and fine-tune them.

💡 What You Will Learn

OpenChat (8,984 stars) is an open-source family of chatbot models known for strong performance with mixed data training. Here is how to run and fine-tune them.

## The short answer **togethercomputer/OpenChat** (8,984 stars, Python) is an open-source library and model family for training and running chatbot models. It pioneered the "mixed" training approach - combining instruction data, preference data, and general conversation - which produced models that punch above their weight class. ## Why OpenChat got attention - **Strong small models**: OpenChat-3.5 (7B) scored competitively against much larger models on many benchmarks - **Simple training recipe**: the mixed-data fine-tuning approach is documented and reproducible - **Easy serving**: OpenAI-compatible API server included - **Local friendly**: 7B models run on consumer GPUs ## Run it locally Option 1 - via Transformers (163,376 stars): ```python from transformers import AutoModelForCausalLM, AutoTokenizer tokenizer = AutoTokenizer.from_pretrained("openchat/openchat-3.5-1210") model = AutoModelForCausalLM.from_pretrained("openchat/openchat-3.5-1210", torch_dtype="auto") ``` Option 2 - serve with the built-in API: ```bash git clone https://github.com/imoneoi/openchat.git cd openchat && pip install -e . python -m openchat.server --model openchat/openchat-3.5-1210 # OpenAI-compatible endpoint at http://localhost:18888 ``` ## Fine-tuning notes - The repo provides a `finetune` script with the exact data mix used for OpenChat-3.5. - LoRA-style efficient fine-tuning is supported for consumer GPUs. - Start from the 7B base and evaluate on your task before scaling up. ## FAQ **Is it free?** Yes - the models and training code are open source (Apache-2.0 for the code). **Can I use it commercially?** Check each model card license; base model licenses vary. **How does it compare to Llama?** OpenChat is often trained on top of Llama/Mistral bases, adding its mixed-data recipe - performance depends on the base model.