| Signal | Claude Opus 4.6 (Fast) | Delta | Grok 4 Fast |
|---|---|---|---|
Capabilities | 100 | -- | |
Benchmarks | 87 | +17 | |
Pricing | 5 | -94 | |
Context window size | 95 | -5 | |
Recency | 100 | +4 | |
Output Capacity | 85 | +11 | |
| Overall Result | 3 wins | of 6 | 2 wins |
Score History
90.4
current score
Claude Opus 4.6 (Fast)
right now
72.5
current score
Anthropic
xAI
Grok 4 Fast saves you $10455.00/month
That's $125460.00/year compared to Claude Opus 4.6 (Fast) at your current usage level of 100K calls/month.
| Metric | Claude Opus 4.6 (Fast) | Grok 4 Fast | Winner |
|---|---|---|---|
| Overall Score | 90 | 73 | Claude Opus 4.6 (Fast) |
| Rank | #6 | #66 | Claude Opus 4.6 (Fast) |
| Quality Rank | #6 | #66 | Claude Opus 4.6 (Fast) |
| Adoption Rank | #6 | #66 | Claude Opus 4.6 (Fast) |
| Parameters | -- | -- | -- |
| Context Window | 1000K | 2000K | Grok 4 Fast |
| Pricing | $30.00/$150.00/M | $0.20/$0.50/M | -- |
| Signal Scores | |||
| Capabilities | 100 | 100 | Claude Opus 4.6 (Fast) |
| Benchmarks | 87 | 70 | Claude Opus 4.6 (Fast) |
| Pricing | 5 | 100 | Grok 4 Fast |
| Context window size | 95 | 100 | Grok 4 Fast |
| Recency | 100 | 96 | Claude Opus 4.6 (Fast) |
| Output Capacity | 85 | 75 | Claude Opus 4.6 (Fast) |
Our score (0-100) is driven by benchmark performance (90%) from Arena Elo ratings, MMLU, GPQA, HumanEval, SWE-bench, and 15+ standardized evaluations. Capabilities and context window serve as tiebreakers (10%). Learn more about our methodology.
Scores 90/100 (rank #6), placing it in the top 98% of all 290 models tracked.
Scores 73/100 (rank #66), placing it in the top 78% of all 290 models tracked.
Claude Opus 4.6 (Fast) has a 18-point advantage, which typically translates to noticeably stronger performance on complex reasoning, code generation, and multi-step tasks.
Grok 4 Fast offers 100% better value per quality point. At 1M tokens/day, you'd spend $10.50/month with Grok 4 Fast vs $2700.00/month with Claude Opus 4.6 (Fast) - a $2689.50 monthly difference.
Both models have comparable response speeds. For most applications, the latency difference is negligible.
When latency matters most: Interactive chatbots, IDE code completion, real-time translation, and user-facing applications where response time directly impacts experience. For batch processing, background summarization, or offline analysis, latency is less critical.
Code generation & review
Higher benchmark score (0/100) indicates stronger performance on coding tasks like generating functions, debugging, and refactoring
Customer support chatbot
Faster response time (speed score 0/100) is critical for user-facing chat. Grok 4 Fast also offers lower per-token costs for high-volume support
Long document analysis
Larger context window (2000K tokens) can process longer documents, contracts, and research papers in a single pass
Batch data extraction
Lower output pricing ($0.50/M) reduces costs when processing thousands of records daily
Creative writing & content
Higher overall composite score (90/100) correlates with better nuance, coherence, and style in long-form content
Image understanding & OCR
Supports vision input - can analyze screenshots, diagrams, photos, and scanned documents directly
Claude Opus 4.6 (Fast) clearly outperforms Grok 4 Fast with a significant 17.900000000000006-point lead. For most general use cases, Claude Opus 4.6 (Fast) is the stronger choice. However, Grok 4 Fast may still excel in niche scenarios.
Best for Quality
Claude Opus 4.6 (Fast)
Marginally better benchmark scores; both are excellent
Best for Cost
Grok 4 Fast
100% lower pricing; better value at scale
Best for Reliability
Claude Opus 4.6 (Fast)
Higher uptime and faster response speeds
Best for Prototyping
Claude Opus 4.6 (Fast)
Stronger community support and better developer experience
Best for Production
Claude Opus 4.6 (Fast)
Wider enterprise adoption and proven at scale
by Anthropic
| Capability | Claude Opus 4.6 (Fast) | Grok 4 Fast |
|---|---|---|
| Vision (Image Input) | ||
| Function Calling | ||
| Streaming | ||
| JSON Mode | ||
| Reasoning | ||
| Web Search | ||
| Image Output |
Anthropic
xAI
Grok 4 Fast saves you $233.04/month
That's 100% cheaper than Claude Opus 4.6 (Fast) at 1,000 tokens/request and 100 requests/day.
Assumes 60% input / 40% output token ratio per request. Actual costs may vary based on your usage pattern.
| Parameter | Claude Opus 4.6 (Fast) | Grok 4 Fast |
|---|---|---|
| Context Window | 1M | 2M |
| Max Output Tokens | 128,000 | 30,000 |
| Open Source | No | No |
| Created | Apr 7, 2026 | Sep 19, 2025 |
Claude Opus 4.6 (Fast) scores 90/100 (rank #6) compared to Grok 4 Fast's 73/100 (rank #66), giving it a 18-point advantage. Claude Opus 4.6 (Fast) is the stronger overall choice, though Grok 4 Fast may excel in specific areas like cost efficiency.
Claude Opus 4.6 (Fast) is ranked #6 and Grok 4 Fast is ranked #66 out of 290+ AI models. Rankings use a composite score combining benchmark performance (90%) from MMLU, GPQA, HumanEval, SWE-bench, and 15+ standardized evaluations, with capabilities and context window as tiebreakers (10%). Scores update hourly.
Grok 4 Fast is cheaper at $0.50/M output tokens vs Claude Opus 4.6 (Fast)'s $150.00/M output tokens - 300.0x more expensive. Input token pricing: Claude Opus 4.6 (Fast) at $30.00/M vs Grok 4 Fast at $0.20/M.
Grok 4 Fast has a larger context window of 2,000,000 tokens compared to Claude Opus 4.6 (Fast)'s 1,000,000 tokens. A larger context window means the model can process longer documents and conversations.