AI chatbots have taken the world by storm—and leading the charge is OpenAI’s ChatGPT. But as powerful as it is, ChatGPT comes with limitations: it runs on the cloud, raises privacy concerns, and isn’t open source.
Whether you're a developer looking to run AI locally, a researcher experimenting with models, or someone just tired of hitting usage limits, you're in luck. The open-source AI world has been booming with local alternatives that give you full control over your chatbot experience—offline, private, and hackable.
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In this article, we’ll explore 10 of the best open-source ChatGPT alternatives you can run 100% locally on your own machine or server.
Why Run AI Locally?
So… why go through the trouble of running a ChatGPT-style model on your own machine when cloud services already work out of the box?
Here are a few good reasons developers and AI enthusiasts are making the switch to local:
- Full Data Privacy: When you run locally, your inputs, outputs, and prompts stay entirely on your device. That means no accidental data leaks, no third-party analytics, and no vague “we may use your input to improve our models” clauses.
- Offline Access: No internet? No problem. Local tools let you generate responses, code, or content even if you’re on a plane, off-grid, or working in a secure environment.
- Open Source and Hackability: Most of the tools on this list are completely open source. That means you can read the code, fork the repo, make changes, and even contribute back.
- Faster Iteration for Developers: If you’re building something on top of a language model, working locally can significantly speed up your development loop.
- Cost Savings Over Time: Local models may require some upfront setup or hardware resources, but if you're frequently using LLMs, running them locally can save serious money in the long run—especially compared to high-usage tiers on commercial platforms.
ChatGPT open source alternatives
1. Gaia by AMD
Gaia is a brand-new, open-source project from AMD that lets you run LLMs entirely on your Windows PC, with or without specialized hardware like Ryzen AI chips. It stands out for its straightforward setup and built-in RAG (Retrieval-Augmented Generation) capabilities—ideal if you want models that can reason over your local data.
Key Features:
- Runs fully locally using the Lemonade SDK from ONNX, with performance optimizations for Ryzen AI processors.
Includes four built-in agents:
- Simple Prompt Completion for basic interactions
- Chaty, a standard chat agent
- Clip, for YouTube Q&A
- Joker, for lighthearted fun
- RAG support via a local vector database, enabling grounded and context-aware responses
Two installer options:
- Mainstream installer for any Windows PC
- Hybrid installer optimized for Ryzen AI hardware
- Offers improved security, low latency, and true offline functionality.
Ideal for:
Windows users who want a powerful, offline-capable LLM assistant—especially those with Ryzen AI hardware, but it works well on any modern PC.
2. Ollama + LLaMA / Mistral / Gemma
URL: https://ollama.com
Ollama is a sleek local runtime for large language models (LLMs) like Meta's LLaMA, Mistral, and Google’s Gemma. It abstracts the complexity of running large models by offering a Docker-like CLI to download, run, and chat.
Why it's great:
- Simple CLI and desktop interface
- Supports multiple open-source models (LLaMA, Mistral, Code LLaMA)
- Fast local inference, even on MacBooks with Apple Silicon
Ideal for: Anyone wanting a no-fuss way to run LLMs locally
3. LM Studio
URL: https://lmstudio.ai
License: MIT
LM Studio is a local GUI application for chatting with LLMs. It supports any GGUF model from Hugging Face or TheBloke and runs inference locally with no internet connection required.
Why it's great:
- Beautiful and intuitive desktop UI
- Easy to import models via drag-and-drop
- Local history and multi-model switching
Ideal for: Non-technical users, developers who want a GUI without the terminal
4. LocalAI
URL: https://github.com/go-skynet/LocalAI
LocalAI is like OpenAI’s API—but fully local. It provides a drop-in replacement for OpenAI-compatible APIs, so you can run your own GPT-like model and use it in apps built for ChatGPT.
Why it's great:
- Fully API-compatible with OpenAI
- Easily deployable with Docker
- Runs GGUF and ONNX models
Ideal for: Developers looking to integrate LLMs into their apps with full control
5. Text Generation Web UI (oobabooga)
URL: https://github.com/oobabooga/text-generation-webui
This tool is a Swiss Army knife for running local LLMs with a full web interface, plugin support, chat history, and more. It supports models like Vicuna, Mistral, Falcon, and others in multiple formats.
Why it's great:
- Feature-rich with chat, instruction, and roleplay modes
- Plugin system for extensions like voice-to-text, memory, and embeddings
- Community-driven and highly customizable
Ideal for: Advanced users and tinkerers
6. PrivateGPT
URL: https://github.com/imartinez/privateGPT
PrivateGPT is built for those who want a fully offline AI chatbot that can even answer questions about your documents without an internet connection. It combines local LLMs with RAG (Retrieval Augmented Generation) features.
Why it's great:
- Totally private, with no API calls
- Drop in your PDFs or DOCs and ask questions
- Great for legal, academic, and corporate users
Ideal for: Data-sensitive users, legal teams, researchers
7. GPT4All
URL: https://gpt4all.io
GPT4All by Nomic AI offers a simple GUI to interact with multiple open-source LLMs on your laptop or desktop. It focuses on smaller, performant models that run well on consumer hardware.
Why it's great:
- Easy one-click installation
- Wide range of supported models (LLaMA, Falcon, etc.)
- Works on Windows, macOS, and Linux
Ideal for: Newbies or developers who want a plug-and-play local LLM
8. Jan (formerly gpt-terminal)
URL: https://github.com/adamyodinsky/TerminalGPT
Jan is an open-source AI assistant designed to run locally with a beautiful macOS-style desktop UI. It supports multiple LLM backends and also provides code assistance.
Why it's great:
- Sleek and responsive UI
- Focused on usability and offline privacy
- Works with Ollama and Hugging Face models
Ideal for: Mac users, designers, and privacy-conscious coders
9. Hermes / KoboldAI Horde
URL: https://github.com/KoboldAI/KoboldAI-Client
Originally built for AI storytelling, KoboldAI supports many open models and works great for dialogue generation, story creation, and roleplay. It can also be used like ChatGPT with the right settings.
Why it's great:
- Tailored for storytelling and dialogue
- Works offline with GGUF and GPT-J based models
- Supports collaborative model usage via Horde network
Ideal for: Writers, fiction creators, hobbyists
10. Chatbot UI + Ollama Backend
URL: https://github.com/mckaywrigley/chatbot-ui
If you love the ChatGPT interface, this is for you. Chatbot UI is a sleek frontend that mimics ChatGPT but can be hooked up to your local Ollama, LocalAI, or LM Studio server.
Why it's great:
- Beautiful ChatGPT-style UI
- Local deployment with backend flexibility
- Self-hosted and configurable
Ideal for: Devs who want a private ChatGPT clone at home
Final Thoughts
AI doesn’t have to live in the cloud. With the rise of open source tools and local-first development, it’s easier than ever to bring ChatGPT-style experiences to your own device—without giving up control or privacy.
Whether you’re a developer experimenting with LLMs, a researcher wanting reproducibility, or someone who just prefers their AI without the surveillance, there’s a local tool out there for you. From lightweight desktop apps to fully customizable self-hosted setups, the options are growing fast—and getting more powerful every month.
Open source gives you freedom: to tweak, to learn, to contribute, and to build something that works exactly the way you want it to. And honestly, that’s what makes this space so exciting.
If you’ve been on the fence about ditching cloud AI, maybe now’s the time to try one of these local alternatives. You might be surprised how far open source has come.
That's a good one, Emmanuel! Nice to know local-run, privacy-first LLM chatbots!