GPTNeo vs. Grok

Overview

GPTNeo is a model released by EleutherAI to try and provide an open source model with capabilities similar to OpenAI's GPT-3 model. One of the earliest such models, GPTNeo was trained on The Pile, Eleuther's corpus of web text.

Initial release: 2021-03-21

Reference

https://huggingface.co/togethercomputer/GPT-NeoXT-Chat-Base-20B

Further Reading

Overview

Grok is the proprietary model family available through xAI's products and API. Grok 4.5 is the current generation, focused on coding, agentic tasks, reasoning, and knowledge work.

xAI introduced Grok in November 2023 and released the weights for Grok-1 under Apache 2.0 in March 2024. Later generations are proprietary and available through Grok, X, and the xAI API. Grok 4.5, released in July 2026, is xAI's current flagship model for software engineering, tool-driven agents, complex reasoning, and professional knowledge work.

Initial release: 2023-11-05

Current generation: Grok 4.5

Reference

https://x.ai/news/grok-4-5

Further Reading

• https://github.com/xai-org/grok-1/tree/main
• https://x.ai/news/grok-4-5