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Alternatives to

5 Best Open Source Alternatives to ChatGPT (2026)

AI chatbot and assistant by OpenAI

ChatGPT starts at $20/mo — these alternatives can save you money.

#1
harbor

Complete pre-wired LLM stack with hundreds of services to explore.

Open Source2.5KAlternative to ChatGPT
Website GitHub
#2
LLMs-from-scratch

Build ChatGPT-like LLMs from scratch with PyTorch.

Open Source87.1KAlternative to ChatGPT
Website GitHub
#3
prompts.chat

Community-driven ChatGPT prompts with open source and self-hosting support.

Open Source150.1KAlternative to ChatGPT
Website GitHub
#4
yek

Fast Rust tool to serialize text files for LLM consumption.

Open Source2.4KAlternative to ChatGPT
GitHub
#5
llm-course

Learn Large Language Models with guided roadmaps and interactive notebooks.

Open Source77.7KAlternative to ChatGPT
Website GitHub

Frequently Asked Questions

What is the best free alternative to ChatGPT?

harbor is the most popular free alternative to ChatGPT, with 2,535 GitHub stars.

Is there an open source version of ChatGPT?

Yes! There are 0 open source alternatives to ChatGPT listed above.

How much does ChatGPT cost?

ChatGPT starts at $20/mo. The alternatives listed above include free and more affordable options.