Grok 4 Heavy
No estimate
No hardware requirements for this model
The weights for this model have not been published, so it cannot be downloaded or run on your own hardware at any size. It is reachable only through its provider, and no graphics card changes that.
On record
Full specification
Everything on record for this model. Most of it describes how it was trained rather than how it runs — useful context for judging how much work went into it, and how it compares with models built at a different scale.
Origin
Who built this model, where, and when it was published.
- Organisation
- xAI
- Organisation type
- Industry
- Country
- United States of America
- Published
- 10 July 2025
What it does
The problem areas the model was built for. A model can carry several of each.
- Domain
- Language
- Task
- Language modeling/generation, Question answering, Mathematical reasoning, Quantitative reasoning, Code generation
Size
How large the model is and how much data it was trained on. Parameters are the figure that decides whether it fits on a given graphics card.
- Training data
- tokens
Availability
Whether you can obtain the model and run it on your own hardware, which is what decides if any of the graphics-card figures on this page apply.
- Weights
- Closed — provider access only
- Model access
- Unreleased
- Training code
- Unreleased
How it is classified
Labels the source dataset applies when tracking notable models, and how confident it is in the entry.
- Why it is tracked
- SOTA improvement
- Record confidence
- Unknown
"Grok 4 Heavy leads USAMO'25 with 61.9%, and is the first to score 50.7% on Humanity's Last Exam (text-only subset), demonstrating unparalleled capabilities in complex reasoning through scaled reinforcement learning and native tool use."
Sources
Where this record came from and when it was last checked.
- Reference
- Grok 4 Heavy - the most powerful version of Grok 4
- Last updated
- 19 February 2026
What the numbers mean
What this model is
Grok 4 Heavy was published by xAI, in the country recorded as United States of America, during July 2025. The category the publisher falls under is industry.
It works in the domain of Language, and is recorded as performing the task of language modeling/generation, Question answering, Mathematical reasoning, Quantitative reasoning, Code generation.
Because the weights are not available, none of the hardware figures elsewhere on this site apply to it.
Training and provenance
Its inclusion criterion: sOTA improvement.
Answers
Grok 4 Heavy — common questions
Grok 4 Heavy— what is it used for?
It works in the domain of Language, and is recorded as handling the task of language modeling/generation, Question answering, Mathematical reasoning, Quantitative reasoning, Code generation. These are the areas it was designed around; they describe intent rather than a hard boundary.
Grok 4 Heavy— what GPU do I need to run it?
None. This is a closed model — its weights were never published, so it cannot be downloaded or run on your own hardware at any price. It is reachable only through its provider.
Grok 4 Heavy— is it open source?
No. Its weights have not been published, so it exists only as a service controlled by its owner.
Grok 4 Heavy— how many parameters does it have?
No parameter count has been published for it, which is why no memory or speed figure appears on this page.
Grok 4 Heavy— who created it?
It was published by xAI, based in United States of America, an organisation categorised as industry.
Grok 4 Heavy— when was it released?
It was published in July 2025.
The other direction
Looking at it from the other side?
This page starts from the model. If you already own a card and want to know everything it will run, start from the hardware instead.