Grok 4.20
xAI's flagship reasoning model with 2M-token context, low hallucination rate, and agentic tool calling — available on Venice with zero retention.
Overview
What is Grok 4.20
Grok 4.20 is xAI's flagship language model, released in March 2026, featuring a 2-million-token context window, vision input, function calling, and reasoning modes. It delivers high accuracy with industry-leading speed and strict prompt adherence, making it ideal for complex, long-form AI tasks.
Running it privately on Venice
Running Grok 4.20 on Venice ensures your prompts are never stored, profiled, or used for training—true zero retention. You get full access to its reasoning, vision, and web search capabilities with end-to-end privacy, ideal for enterprises and developers who demand sovereignty over their AI workflows.
Assessment
Strengths and limitations
- Industry-leading 2-million-token context window, enabling processing of entire codebases or lengthy documents in a single pass.
- Lowest hallucination rate among major models, with strict prompt adherence and high factual precision.
- Supports vision, function calling, reasoning, and web search—ideal for agentic and real-time workflows.
- Available in multiple variants: reasoning, non-reasoning, and multi-agent modes for tailored use cases.
- High throughput: up to 828 output tokens per second in optimized environments.
- Proprietary and closed weights—cannot be self-hosted or fine-tuned locally.
- Higher pricing for long prompts (≥200K tokens), which may affect cost-sensitive applications.
- No end-to-end encryption or TEE support on Venice, limiting extreme-security use cases.
- Knowledge cutoff is September 1, 2025—may lack awareness of events after that date.
Capabilities
What it supports
- Tool use / function calling
- Vision (image input)
- Reasoning
- Web search
- Code-optimized
- Structured output (JSON schema)
- Audio input
- Video input
- Multiple image inputs
- Log probabilities
Specifications
Datasheet
- Maker
- xAI
- Released
- March 10, 2026 (API general availability)
- Modality
- Text, image → text
- Architecture
- Not disclosed
- Parameters
- Not disclosed
- Open weights
- No
- Context window
- 2,000K tokens
- Max output
- 128K tokens
- Capabilities
- Vision, Function calling, Reasoning, Web search
- Privacy on Venice
- Private — zero retention
- Available on Venice since
- Mar 2026
- License
- Proprietary
API
Call it from your code
Venice exposes an OpenAI-compatible API. Point your base URL at Venice and pass the model id.
curl https://api.venice.ai/api/v1/chat/completions \
-H "Authorization: Bearer $VENICE_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "grok-4-20",
"messages": [{ "role": "user", "content": "Explain quantum tunneling simply." }]
}'Pricing
What it costs on Venice
Billed per token on Venice: $1.42 per 1M input tokens and $2.83 per 1M output tokens.
New Venice accounts include a free daily allowance and 500 welcome credits — no credit card required.
Alternatives
How it compares
| Model | Max context | Strongest at | Open weights | Price (Venice) |
|---|---|---|---|---|
| Grok 4.20 | 2M tokens | Long-context reasoning, low hallucination | No | $1.42 in · $2.83 out / 1M |
| Claude Opus 5 | 1M tokens | Coding, user satisfaction | No | $6 in · $30 out / 1M |
| Grok 4.5 | 500K tokens | Coding, agentic tasks | No | $2.27 in · $6.80 out / 1M |
| DeepSeek V4 Flash 0731 | 1M tokens | Speed, cost efficiency | No | $0.17 in · $0.35 out / 1M |
Flagship model with largest context window and agentic capabilities.
Use cases
What it is good for
- 01Enterprise knowledge retrieval across massive document sets.
- 02Agentic workflows with tool use and multi-agent debate for decision accuracy.
- 03Real-time analysis of social media trends via integration with X (Twitter).
- 04High-precision customer support bots requiring strict adherence to guidelines.
- 05Long-form content generation, summarization, and legal or financial document review.
Prompting
Getting better results
Use the reasoning variant for complex logic or multi-step tasks; use non-reasoning for faster, direct responses.
Include images in queries when context relies on visual data—Grok 4.20 supports multiple image inputs.
Enable web search to pull in real-time data, especially useful for trending topics on X.
For long documents, structure input with clear section headers to improve model navigation.
Pin to checkpoint `grok-4.20-0309-reasoning` for consistent behavior over time.
Version history
Initial release
Enhanced for coding and agentic tasks
Current flagship — 2M context, reasoning modes, multi-agent
FAQ
Frequently asked questions
Grok 4.20 is xAI's flagship language model, released in March 2026, featuring a 2-million-token context window, vision input, function calling, and multiple reasoning modes. It is optimized for high accuracy, low hallucination, and complex agentic workflows.
On Venice, Grok 4.20 costs $1.42 per 1M input tokens and $2.83 per 1M output tokens. Cached input is $0.23 per 1M tokens. Rates increase for prompts over 200K tokens.
No. Grok 4.20 is a proprietary model developed by xAI. It is not open source, and weights are not publicly available for self-hosting or fine-tuning.
Yes. Grok 4.20 supports image input and can process multiple images per request. It is capable of analyzing charts, diagrams, and other visual content as part of its multimodal reasoning.
Yes. Grok 4.20 supports function calling and structured JSON output, enabling integration with external tools, APIs, and databases for agentic workflows.
Grok 4.20 has a 2-million-token context window—the largest among current flagship models—allowing it to process extremely long documents, codebases, or conversations in a single pass.
Grok 4.20 excels in long-context tasks, speed, and cost efficiency, while Claude Opus 5 leads in coding benchmarks and user satisfaction (Chatbot Arena). Choose Grok for agentic, real-time workflows; Claude for precision coding and nuanced dialogue.
Yes. Grok 4.20 includes built-in web search capabilities, allowing it to pull real-time information, especially useful for trending topics on X (Twitter) and up-to-date research.
No. While Grok is marketed as less sanitized than some competitors, it is not uncensored. It follows xAI's safety policies and may filter or refuse certain content based on guidelines.
Run Grok 4.20 privately
No prompt logging. No data used for training.