We Compare AI

Open Source AI

Core Concepts
Simple Definition

AI models whose weights and (sometimes) training code are publicly released, allowing anyone to run, modify, and build on them.

Full Explanation

Open source AI (Meta's LLaMA, Mistral, Stable Diffusion) contrasts with closed models (GPT-4, Claude, Gemini) where the weights are proprietary. Open models can be run locally (full privacy), fine-tuned for specific use cases, and deployed without per-token API fees. The quality gap between open and closed models has narrowed significantly — LLaMA 3.1 405B is competitive with GPT-4o.

Last verified: 2026-03-30← Back to Glossary