After making a strong entrance into the AI scene, xAI quickly became one of the most talked-about companies in the industry thanks to its conversational model Grok. While many users expected an incremental Grok 3.5 release, xAI skipped straight ahead to Grok 4, marking a major leap in scale and capability.
So what changed? And why is Grok 4 considered one of the most powerful models ever created? Let’s break down the key improvements, benchmarks, and what this means for users and developers.
From Grok 3 to Grok 4: A Giant Leap in Computation
Founded by Elon Musk, xAI has built its reputation around developing AI systems tightly integrated with the X platform (formerly Twitter). Grok 4 represents the company’s largest advancement yet, boasting up to 10× more computational power than its predecessor, Grok 3.
According to xAI, the model delivers significant gains in academic, mathematical, and reasoning benchmarks. The Grok 4 family currently includes only two variants — Grok 4 and Grok 4 Heavy — with the latter designed for multi-agent reasoning and complex task execution.
While Grok 4 Heavy utilizes multiple cooperating agents, the standard Grok 4 functions as a single-agent system optimized for structured reasoning and long-form responses.
Benchmark Results: Humanity’s Last Exam and Beyond
One of Grok 4’s most striking achievements comes from the Humanity’s Last Exam (HLE) benchmark — a demanding suite of 2,500 PhD-level questions covering mathematics, physics, chemistry, linguistics, and engineering.
- Grok 4 (with tools): ≈ 38.6 % accuracy
- Grok 4 Heavy: ≈ 50.7 % accuracy
- Grok 4 (no tools): ≈ 26.9 % accuracy
When tool use (such as code execution) is enabled, accuracy almost doubles — a testament to the effectiveness of xAI’s tool-enhanced reasoning design.
Context Length and Model Design
Grok 4 supports 128 K tokens in the chat interface and 256 K tokens via API — sufficient for long reasoning chains, though smaller than the 1 million-token window offered by Gemini 2.5 Pro.
This means developers must still structure and trim their prompts carefully. The design trade-off favors faster inference and improved tool integration over raw context length.
STEM and Academic Benchmarks
In widely used STEM and reasoning evaluations, Grok 4 performs exceptionally well, outperforming most major competitors:
| Benchmark | Grok 4 (No Tools) | Grok 4 Heavy | Best Competitor |
|---|---|---|---|
| GPQA | 79.6 – 86.4 % | 87.5 % | Claude Opus ≈ 88.9 % |
| AIME 25 | 75.5 – 98.8 % | 100 % | Gemini 2.5 Pro ≈ 91.7 % |
| HMMT 25 | 58.3 – 82.5 % | 96.7 % | GPT-4 (o3) ≈ 90 % |
| USAMO 25 | 21.7 – 49.4 % | 61.9 % | Claude Opus ≈ 60 % |
Across most tests, Grok 4 meets or exceeds the performance of Claude Opus, Gemini 2.5 Pro, and GPT-4 (o3) — positioning xAI firmly among the top LLM developers.
ARC-AGI: Abstract Reasoning Mastery
The ARC-AGI benchmark evaluates a model’s ability to reason abstractly and generalize to unseen problems. Here, Grok 4 achieved:
- ARC-AGI v1: 66.6 % (score higher than all known peers)
- ARC-AGI v2: 15.9 %, outperforming Claude 4 Opus (8.6 %)
These results highlight Grok 4’s strong multi-step reasoning abilities — particularly in complex symbolic and logic-based tasks.
Real-World Simulation: Vending-Bench Test
xAI also evaluated Grok 4 using Vending-Bench, a business-management simulation designed to test long-term decision-making. The model had to manage inventory, adjust pricing, and maintain supplier relationships across 300 rounds.
| Rank | Model | Net Worth | Units Sold |
|---|---|---|---|
| 1 | Grok 4 | $4,694 | 4,569 |
| 2 | Claude Opus 4 | $2,077 | 1,412 |
| 3 | Human Baseline | $ 844 | 344 |
| 4 | Gemini 2.5 Pro | $ 789 | 356 |
| 5 | GPT-4 (o3) | $1,843 | 1,363 |
Grok 4 more than doubled the economic output of its nearest rival and maintained stable performance throughout the entire 300-turn simulation — a rare achievement among large models.
Subscription Plans and Access
xAI now offers multiple subscription tiers under the X Premium ecosystem:
- Free Tier: Limited access to Grok 3
- SuperGrok Plan ($30 / month): Expanded access to Grok 3 and Grok 4
- SuperGrok Heavy ($300 / month): Full access to Grok 4 Heavy, Grok 4, and Grok 3
Users can interact with Grok directly through X (Premium +), Grok.com, or the xAI API.
How to Access Grok 4
1. Via X App (formerly Twitter)
Open the X app or visit x.com, then tap the Grok icon (bottom navigation on mobile or sidebar on desktop). Grok 4 is the default model, and you can switch between versions at any time.
2. Via Grok.com
Head to https://grok.com, sign up or log in, and start chatting directly with the latest model in a dedicated interface.
3. Via xAI API
Developers can integrate Grok 4 into their own apps or workflows through the xAI API. After applying for developer access, you’ll receive an API key and documentation for integration.
Grok Imagine: Free AI Image and Video Generator
xAI has also announced that its generative tool Grok Imagine is now free for all users.
This multimodal AI feature turns text prompts into images and short videos, combining visual creativity with Grok’s language understanding.
Initially limited to paid SuperGrok or Premium Plus members, the feature has now been opened to the public — although some advanced options remain paid.
For example, the controversial “Spicy Mode” (capable of generating explicit content) is still locked behind a premium tier.
How to Use Grok Imagine
- Open the Grok app on your smartphone.
- Sign in and open a chat window.
- Tap the Imagine tab (top right corner).
- Enter a text prompt describing your desired scene, style, or action.
- Optionally, upload an image from your gallery for AI-powered editing.
Grok Imagine allows users to generate voice-over visuals and short animated clips directly from text. It represents xAI’s push to compete in the growing creative-AI market against tools like Midjourney, Runway, and Pika.
Final Thoughts
With Grok 4 and Grok Imagine, xAI is pushing beyond chatbots into the frontier of multimodal reasoning and creative AI.
The model’s impressive scores in academic benchmarks and real-world simulations make it a serious contender to OpenAI, Anthropic, and Google.
Still, like any AI benchmark, numbers don’t tell the whole story — real-world adoption and developer feedback will ultimately define Grok 4’s place in the AI landscape.
For more AI insights and tech guides, visit our Free Screen Size Checker tool at FreeDownloadTools.
