Incremental update to Grok 4 with improved reasoning, multimodal understanding, and reduced hallucination rates. Fast variant (2M token context) available for agentic workflows. Released November 17, 2025.
Context window
256K
tokens
Release date
17 November 2025
Access:APIHostedDeployment:โ Cloud
Overview
Access & deployment
APIHosted
Cloud
Weights: Closed
Key parameters
๐ Context: 256K
โ Tools
๐ฅ Input: text, image
Technical specification
Context window
256K
tokens
License
Proprietary
Features:โ Tool use
Modalities
โฌ Input
textimage
โฌ Output
text
Capabilities and applications
Native model capabilities
Reasoning
The model's ability to reason logically and solve complex problems.
Category: reasoning
Multi-step reasoning
Carrying out multi-step chains of reasoning across long, complex tasks.
Category: reasoning
Coding
Generating, analysing and modifying code in many programming languages. Covers writing functions, debugging, refactoring, code review, and creating tests. Measured by benchmarks such as HumanEval and SWE-bench.
Category: coding
Image understanding
Analysing and interpreting the content of images.
Category: vision
Multilingual
Competence in many natural languages (from a few to over a hundred): understanding, generation, translation, and code-switching within a single conversation. Frontier models support a wide range of languages with comparable quality.
Category: language
Long context
Support for large context windows โ tens to hundreds of thousands (or millions) of input tokens. Enables analysis of entire codebases, long documents, and many parallel conversations without losing earlier information. GPT-5.1 supports 400,000 tokens.
Category: language
Planning
Forming and executing action plans for complex tasks.
Category: planning
Function Calling
Category: planning
Structured output
Producing data in structured formats such as JSON.
Category: structured_generation
