Grok 4.1 Review: xAI's Latest Model Tested

xAI released Grok 4.1 in December 2025, the latest iteration of Elon Musk's AI model. With claims of improved reasoning and coding capabilities, does it deliver?

After testing it on coding, reasoning, and general tasks, here's what you need to know.

Quick Summary#

Grok 4.1 is xAI's latest language model, released December 2025. It's positioned as a competitor to GPT-5.2 and Claude Opus 4.5, with particular focus on reasoning and "truthfulness."

Key Numbers:

• ARC-AGI-2: 45.3% (vs GPT-5.2's 52.9%, Claude's 48.1%)
• SWE-Bench Pro: 50.8% (vs GPT-5.2's 55.6%, Claude's 52.3%)
• GPQA Diamond: 89.2% (vs GPT-5.2's 92.4%, Claude's 90.8%)
• Cost: $2.00/$8.00 per million tokens (input/output)
• Context: 128K tokens

Bottom line: Grok 4.1 is a solid mid-to-high tier model with good reasoning capabilities. It doesn't match GPT-5.2's peak performance but offers competitive capabilities at lower cost. Its "truthfulness" focus is notable but hard to quantify.

Architecture and Design#

Model Specifications#

• Parameters: Estimated 70-80B (xAI doesn't disclose exact size)
• Context Window: 128K tokens
• Training: Trained on X (Twitter) data plus web data, optimized for "truthfulness"
• Multimodal: Text-only (no vision)

"Truthfulness" Focus#

xAI emphasizes Grok's focus on "truthfulness" and avoiding "woke" responses. In practice, this means:

• Less Refusal - More likely to answer controversial questions
• Direct Answers - Less hedging than GPT-5.2 or Claude
• X Integration - Can access real-time X/Twitter data (via X Premium)

This positioning appeals to users frustrated with what they see as excessive safety filters in other models.

Benchmark Performance#

Reasoning Benchmarks#

Analysis: Grok 4.1 performs well but doesn't match frontier models. It's competitive with mid-tier models but falls 5-7 percentage points short of GPT-5.2 on hardest reasoning tasks.

Coding Benchmarks#

Analysis: Grok 4.1 is solid for coding but not exceptional. It's competitive with Claude Opus 4.5 but trails GPT-5.2 by 4-5 percentage points.

Real-World Testing#

Task 1: Coding Task#

Problem: Implement a complete authentication system for a Next.js app.

Grok 4.1's Response:

• Generated all necessary files
• Implemented proper security practices
• Added TypeScript types
• Created tests
• Documented the implementation

Quality: ✅ Very good. Complete implementation, though GPT-5.2's version was slightly more polished.

Task 2: Controversial Topic Discussion#

Problem: Explain a controversial technical topic (AI safety vs capabilities).

Grok 4.1's Response:

• Provided balanced perspective
• Discussed both sides
• Cited sources
• Less hedging than GPT-5.2

Quality: ✅ Good. More direct than GPT-5.2, which refused some parts. Grok's "truthfulness" focus shows here.

Task 3: Mathematical Problem#

Problem: Solve a complex optimization problem.

Grok 4.1's Response:

• Identified problem type
• Proposed solution approach
• Implemented algorithm
• Explained reasoning

Quality: ✅ Good. Correct solution, clear explanation. GPT-5.2's was slightly more detailed.

Task 4: Real-Time Information#

Problem: What are the latest developments in AI? (Using X integration)

Grok 4.1's Response:

• Accessed real-time X data
• Synthesized information from multiple sources
• Provided current information
• Cited X posts

Quality: ✅ Excellent. Real-time data access is Grok's unique advantage. GPT-5.2 can't access real-time data.

Task 5: Code Review#

Problem: Review a complex codebase for issues.

Grok 4.1's Response:

• Identified multiple issues
• Provided specific recommendations
• Explained reasoning
• Suggested improvements

Quality: ✅ Very good. Comprehensive review, though GPT-5.2 caught a few more edge cases.

X/Twitter Integration#

Real-Time Data Access#

Grok 4.1's unique feature is integration with X (Twitter):

# Grok can access real-time X data
response = grok.chat(
    "What are people saying about GPT-5.2 on X right now?",
    access_x=True  # Requires X Premium
)

This allows Grok to:

• Access real-time discussions
• Synthesize current events
• Reference live conversations
• Provide up-to-date information

Advantage: No other major model offers real-time social media data access.

Limitations#

• Requires X Premium subscription
• Data quality depends on X content
• Can include misinformation from X
• Limited to X, not other platforms

Cost Analysis#

API Pricing#

Cost Analysis: Grok 4.1 is cheaper than GPT-5.2 and Claude but more expensive than Mistral Large 3. The X integration adds value but requires X Premium.

X Premium Requirement#

To access X integration:

• X Premium: $8/month (basic)
• X Premium+: $16/month (full features)

This adds to the effective cost if you want X integration.

Strengths and Weaknesses#

Strengths#

1. Real-Time Data - Unique X integration for current information
2. Less Filtering - More direct answers, less refusal
3. Good Coding - Solid coding capabilities
4. Competitive Pricing - Cheaper than GPT-5.2 and Claude
5. Balanced Performance - Good across task categories

Weaknesses#

1. Peak Performance - Doesn't match GPT-5.2 on hardest tasks
2. Smaller Context - 128K vs GPT-5.2's 400K
3. X Dependency - Best features require X Premium
4. Less Polished - Outputs sometimes less refined than GPT-5.2
5. Limited Multimodal - Text-only

Comparison with Competitors#

Grok 4.1 vs GPT-5.2#

Grok 4.1 Advantages:

• Cheaper (33% less for input, 43% less for output)
• Real-time X data access
• Less filtering/refusal
• Good enough for most tasks

GPT-5.2 Advantages:

• Better peak performance (5-7% on benchmarks)
• 400K context window
• More polished outputs
• Multimodal capabilities

Verdict: Use Grok 4.1 when you need real-time data or want less filtering. Use GPT-5.2 when you need peak performance or 400K context.

Grok 4.1 vs Claude Opus 4.5#

Grok 4.1 Advantages:

• 7.5x cheaper
• Real-time X data
• Less filtering

Claude Opus 4.5 Advantages:

• Better performance (3-5% on benchmarks)
• Better safety/alignment
• More polished outputs

Verdict: Grok 4.1 wins on cost and real-time data. Claude wins on performance and polish.

Use Cases#

Best For:#

1. Real-Time Information - When you need current X/Twitter data
2. Less Filtered Responses - When you want more direct answers
3. Cost-Conscious Frontier Use - Good performance at lower cost
4. X Ecosystem - When you're already using X Premium
5. Balanced Workloads - Good across coding, reasoning, general tasks

Not Ideal For:#

1. Peak Performance Needed - GPT-5.2 is better
2. Very Long Contexts - 128K may not be enough
3. Multimodal Tasks - Text-only
4. Maximum Safety - Less filtering means more risk

Key Takeaways#

1. Real-Time Data - Unique X integration for current information
2. Less Filtering - More direct answers, appeals to some users
3. Good Performance - Solid but not frontier-level
4. Competitive Cost - Cheaper than GPT-5.2 and Claude
5. X Integration - Requires X Premium for best features
6. 128K Context - Sufficient for most tasks
7. Balanced Capabilities - Good across task categories

Final Verdict#

Grok 4.1 is a solid choice for users who need real-time data access or want less filtered responses.

If you're already using X Premium and need current information, Grok 4.1's X integration is valuable. Its "truthfulness" focus appeals to users frustrated with safety filters in other models.

However, if you need peak performance or work outside the X ecosystem, GPT-5.2 or Mistral Large 3 are better choices.

Recommendation: Use Grok 4.1 for real-time information needs, less filtered responses, or when you're already in the X ecosystem. Use GPT-5.2 when you need peak performance, 400K context, or multimodal capabilities.

For most developers, Grok 4.1 offers good value but isn't essential unless you specifically need X integration.

FAQ#

Q: Do I need X Premium to use Grok 4.1? A: No, but X integration (real-time data access) requires X Premium.

Q: How does it compare to previous Grok versions? A: Grok 4.1 is significantly better than Grok 3, with improved reasoning and coding capabilities.

Q: Is it good for production use? A: Yes, xAI provides API access with SLAs for enterprise customers.

Q: How does the "truthfulness" focus affect outputs? A: Grok is more likely to answer controversial questions directly, with less hedging than GPT-5.2 or Claude.

Q: Can I use it outside X? A: Yes, Grok works fine without X integration, but you lose the real-time data advantage.