Grok 4.5 by SpaceXAI is a frontier model for coding, agentic tasks, and knowledge work with configurable reasoning, 500k context, and built-in tools.
Capabilities, design details, and architectural traits
Grok 4.5 is SpaceXAI's flagship model, positioned as the most intelligent and fastest model the company has built. It was trained in SpaceXAI's Memphis data centers using new datasets spanning science, engineering, and math, and is designed as a workhorse for coding, agentic tool calling, and routine knowledge work.
| Trait | Detail |
|---|---|
| Configurable reasoning | Low, medium, or high effort selectable via reasoning_effort, defaulting to high |
| 500k token context window | Supports long conversations and extended agent loops with context compaction |
| Built-in tool suite | Function calling, web search, X search, and code execution available as server-side tools |
| Minimal hallucinations | Explicitly listed as a defining model characteristic alongside agentic tool calling |
| Grok Build default | Serves as the default model for SpaceXAI's coding agent on both API and CLI |
| Office add-in integration | Default model in Word, PowerPoint, and Excel add-ins |
| Twice greater token efficiency | Claimed relative to other leading models, reducing per-task token cost |
Grok 4.5 exposes reasoning_effort as a first-class parameter, letting developers trade latency for depth on a per-request basis. Its tool ecosystem is tightly coupled: web search and X search provide realtime data beyond the knowledge cutoff, while code execution enables in-context programmatic reasoning for coding and math tasks.
Beyond the xAI API, Grok 4.5 ships as the default model in Grok Build (SpaceXAI's coding agent), in Cursor on all plans, and in Office add-ins. It is also accessible through model gateways including OpenRouter, Vercel, Cloudflare, Snowflake, and Databricks Mosaic.
Independent evaluations · Artificial Analysis
Evaluate specifications, pricing, and independent benchmark indices
| Model Details | |||
|---|---|---|---|
| General Info | |||
| Provider | SpaceXAI | Anthropic | Anthropic |
| Release Date | July 8, 2026 | July 24, 2026 | June 9, 2026 |
| Knowledge Cutoff | - | May 2026 | - |
| Context & Limits | |||
| Context Window | - | 1M | 1M |
| Pricing (per 1M tokens) | |||
| Input Pricing | $2 Best Input Pricing | $5 | $10 |
| Output Pricing | $6 Best Output Pricing | $25 | $50 |
| Modalities | |||
| Inputs | text | textimage | textimagefile |
| Outputs | text | text | text |
| Benchmarks (0-100) | |||
| Intelligence Index | 55.8 | 63.1 Best Intelligence Index | 62.1 |
| Coding Index | 72.4 | 78.0 Best Coding Index | 76.5 |
| Agentic Index | 48.9 | 59.2 Best Agentic Index | 56.6 |
Graduate-level reasoning and expert Q&A evaluation.
Extremely difficult logical reasoning and knowledge.
Logical reasoning over long context windows.
Independent evaluation data provided by Artificial Analysis. To view the latest benchmarks and full details, visit their official site.
