# Grok 1

> xAI's first model: a 314B-parameter Mixture-of-Experts base model, later open-sourced under Apache 2.0.

- Maker: xAI (Grok)
- Line: Grok (flagship)
- Canonical page: https://ai-tldr.dev/models/grok-1/
- Updated: 2026-06-18

## In short

Grok 1 is xAI's first model: a 314B-parameter Mixture-of-Experts base model, later open-sourced under Apache 2.0. xAI (Grok) released it on 3 November 2023 as an open-weight model. It has a 8,192-token context window. You can use it through xAI (open weights, GitHub) and Hugging Face (open weights).

## Facts

| Fact | Value | Source |
| --- | --- | --- |
| Context window | 8,192 tokens (max output Not separately specified by xAI (shares the 8,192-token sequence length)) | [1] |
| Licence | Apache-2.0 · open weights | [1] |
| Released | 3 November 2023 | [2] |
| Parameters | 314B total (Mixture-of-Experts; 2 of 8 experts active per token, ~25% of weights) | [1] |
| Knowledge cutoff | October 2023 | [1] |

## Sources

1. [Grok-1 — Hugging Face model weights](https://huggingface.co/xai-org/grok-1)
2. [Open Release of Grok-1 — xAI announcement](https://x.ai/news/grok-os)

## Overview

Grok 1 is the first model from xAI, Elon Musk's AI company, announced on November 3, 2023. xAI presented it as a very early beta — in their own words, "the best we could do with 2 months of training" — and seeded it to a small set of US users before rolling it into the X (formerly Twitter) Premium+ subscription tier. Grok 1 was the engine behind the original Grok chatbot, pitched as a witty assistant with real-time access to information on X.

Under the hood, Grok 1 is a large Mixture-of-Experts (MoE) language model with 314 billion total parameters. For any given token it routes through 2 of its 8 expert networks, so only about a quarter of the weights are active at inference time. It has a 64-layer Transformer architecture, an 8,192-token context window, and a pre-training data cutoff of October 2023. At launch, xAI reported that Grok 1 outperformed GPT-3.5 and Llama 2 70B on standard benchmarks while trailing larger frontier models like GPT-4.

On March 17, 2024, xAI open-sourced Grok 1, releasing the network architecture and full weight parameters under the permissive Apache 2.0 license on GitHub and Hugging Face. At 314B parameters it was, at the time, the largest open-weights MoE model publicly available. The released checkpoint is the unrefined base model from pre-training, not the chat-tuned version that ran in the product, so running it requires substantial GPU memory and additional fine-tuning to be useful as an assistant.

## Benchmarks

- MMLU (5-shot): 73% ([source](https://x.com/ArtificialAnlys/status/1769502975242961301))
- HumanEval (coding, pass@1): 63.2% ([source](https://www.promptingguide.ai/models/grok-1))
- Hungarian national high school math exam (hand-graded): 59% ([source](https://www.promptingguide.ai/models/grok-1))

## Strengths

- Open weights under a fully permissive Apache 2.0 license — free to use, modify, and self-host
- Very large 314B-parameter Mixture-of-Experts design, the largest open MoE model when released
- Sparse activation (only ~25% of weights per token) keeps inference cheaper than a dense 314B model would be
- Strong-for-its-era results: beat GPT-3.5 and Llama 2 70B on several public benchmarks at launch
- Full architecture and JAX/Rust reference inference code published, useful for research and study

## Best for

- Research into large-scale Mixture-of-Experts architectures and sparse inference
- A base model for teams that want to fine-tune their own assistant on permissively-licensed weights
- Historical and educational study of xAI's first-generation model
- Self-hosted experimentation where data must stay on-premises and an open license is required

## How to access

- [xAI (open weights, GitHub)](https://github.com/xai-org/grok-1) — model id `grok-1`
- [Hugging Face (open weights)](https://huggingface.co/xai-org/grok-1) — model id `xai-org/grok-1`

## Grok (flagship) versions

- [Grok 4.3](https://ai-tldr.dev/models/grok-4-3/) (30 April 2026)
- [Grok 4.20](https://ai-tldr.dev/models/grok-4-20/) (March 2026)
- [Grok 4.1](https://ai-tldr.dev/models/grok-4-1/) (17 November 2025)
- [Grok 4](https://ai-tldr.dev/models/grok-4/) (9 July 2025)
- [Grok 3](https://ai-tldr.dev/models/grok-3/) (17 February 2025)
- [Grok 2](https://ai-tldr.dev/models/grok-2/) (20 August 2024)
- [Grok 1.5](https://ai-tldr.dev/models/grok-1-5/) (15 May 2024)
- Grok 1 (3 November 2023) — this page

## FAQ

### When was Grok 1 released, and is it still in use?

xAI announced Grok 1 on November 3, 2023 as an early beta, available through X Premium+. It has since been superseded by Grok 1.5 (May 2024) and later Grok models. The base weights remain freely available as an open-weights release, but the hosted Grok chatbot now runs on much newer versions.

### Are Grok 1's weights really open source?

Yes. On March 17, 2024, xAI published the full network architecture and weight parameters on GitHub and Hugging Face under the Apache 2.0 license, making it free to use, modify, and self-host. At 314B parameters it was the largest open Mixture-of-Experts model available at the time.

### How big is Grok 1 and what architecture does it use?

Grok 1 is a Mixture-of-Experts (MoE) Transformer with 314 billion total parameters. It has 8 experts and activates 2 of them (about 25% of the weights) for each token. It uses 64 layers, an 8,192-token context window, rotary position embeddings, and a 131,072-token SentencePiece vocabulary.

### Can I call Grok 1 through an API?

There was never an official xAI pay-as-you-go API for Grok 1. It was originally accessible only via an X Premium+ subscription, and the open-weights release is meant to be downloaded and self-hosted. Note that the released checkpoint is the raw pre-training base model — it was not chat- or instruction-tuned, so it needs fine-tuning to behave like an assistant.

## Links

- [xAI — official site](https://x.ai)
- [Open Release of Grok-1 — xAI announcement](https://x.ai/news/grok-os)
- [xai-org/grok-1 — GitHub (open weights & code)](https://github.com/xai-org/grok-1)
- [Grok-1 — Hugging Face model weights](https://huggingface.co/xai-org/grok-1)
- [Grok-1 — Prompt Engineering Guide (specs & benchmarks)](https://www.promptingguide.ai/models/grok-1)
- [Artificial Analysis — Grok-1 MMLU & MoE details](https://x.com/ArtificialAnlys/status/1769502975242961301)
- [xAI introduces LLM Grok — InfoQ](https://www.infoq.com/news/2023/11/xai-grok/)
- [Grok (chatbot) — Wikipedia](https://en.wikipedia.org/wiki/Grok_(chatbot))

Source: AI/TLDR LLM registry, https://ai-tldr.dev/models/grok-1/