Grok (xAI)

Overview

xAI is an AI company founded by Elon Musk in 2023. They develop the Grok series, characterized by real-time access to X (Twitter) data and minimally filtered responses. As of 2026, flagships are Grok 4 and Grok 4.1 Fast, with industry-leading 2M token context.

Latest Models: Grok 4 / 4.1 Fast

Lineup

Model	Context	Input	Output	Notes
Grok 4	256K	$3/M	$15/M	Always-on reasoning, flagship
Grok 4.1 Fast	2M	$0.20/M	$0.50/M	Ultra low-cost, max context
Grok 3	131K	$3/M	$15/M	Previous gen
Grok 4.2	—	—	—	Public beta

Key Features

1. 2M Token Context (Industry-Leading)

Grok 4.1 Fast supports a 2,000,000 token context, exceeding GPT-5 mini, Gemini Flash, and every Anthropic model.

2. Unbeatable Low Cost

Grok 4.1 Fast at $0.20 / $0.50 per 1M tokens — cheaper than GPT-5 mini and Gemini 2.5 Flash.

3. Unified Architecture

Grok 4 Fast blends reasoning and non-reasoning modes into a single model with SOTA cost-efficiency.

4. X (Twitter) Real-Time Integration

The only major LLM with direct reference to real-time X posts and trends.

5. DeepSearch

Multi-source research feature available even on the free tier, combining X real-time data with web search.

6. Aurora (Image Generation)

xAI's image generation model, usable directly in Grok.

7. Always-On Reasoning

Grok 4 ships with always-on reasoning — no need to explicitly enable thinking mode.

Plans

Plan	Monthly	Highlights
X (Free)	$0	Basic Grok, DeepSearch
X Premium	$8	Extended Grok access
X Premium+	$16	Full Grok, Aurora
SuperGrok	$30	Grok 4, top tier
xAI API	Pay-per-use	Developer API

Strengths

✅ 2M token context (industry-leading)
✅ Grok 4.1 Fast is one of the cheapest reasoning models
✅ Real-time X data access (unique)
✅ Always-on reasoning
✅ Unified architecture
✅ Aurora image generation
✅ Minimally filtered responses

Weaknesses

❌ Limited Japanese support
❌ Immature ecosystem
❌ Knowledge cutoff (November 2024)
❌ High X dependency
❌ Relaxed safety filters — caution for enterprise use

Official Resources

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