| Signal | GPT-5.1-Codex-Max | Delta | Grok 4.1 Fast |
|---|---|---|---|
Capabilities | 100 | -- | |
Benchmarks | 88 | +13 | |
Pricing | 90 | -9 | |
Context window size | 89 | -11 | |
Recency | 100 | -- | |
Output Capacity | 85 | +11 | |
| Overall Result | 2 wins | of 6 | 2 wins |
Score History
87.8
current score
GPT-5.1-Codex-Max
right now
78
current score
OpenAI
xAI
Grok 4.1 Fast saves you $580.00/month
That's $6960.00/year compared to GPT-5.1-Codex-Max at your current usage level of 100K calls/month.
| Metric | GPT-5.1-Codex-Max | Grok 4.1 Fast | Winner |
|---|---|---|---|
| Overall Score | 88 | 78 | GPT-5.1-Codex-Max |
| Rank | #14 | #52 | GPT-5.1-Codex-Max |
| Quality Rank | #14 | #52 | GPT-5.1-Codex-Max |
| Adoption Rank | #14 | #52 | GPT-5.1-Codex-Max |
| Parameters | -- | -- | -- |
| Context Window | 400K | 2000K | Grok 4.1 Fast |
| Pricing | $1.25/$10.00/M | $0.20/$0.50/M | -- |
| Signal Scores | |||
| Capabilities | 100 | 100 | GPT-5.1-Codex-Max |
| Benchmarks | 88 | 76 | GPT-5.1-Codex-Max |
| Pricing | 90 | 100 | Grok 4.1 Fast |
| Context window size | 89 | 100 | Grok 4.1 Fast |
| Recency | 100 | 100 | GPT-5.1-Codex-Max |
| Output Capacity | 85 | 75 | GPT-5.1-Codex-Max |
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 88/100 (rank #14), placing it in the top 96% of all 290 models tracked.
Scores 78/100 (rank #52), placing it in the top 82% of all 290 models tracked.
GPT-5.1-Codex-Max has a 10-point advantage, which typically translates to noticeably better performance on complex reasoning, code generation, and multi-step tasks.
Grok 4.1 Fast offers 94% better value per quality point. At 1M tokens/day, you'd spend $10.50/month with Grok 4.1 Fast vs $168.75/month with GPT-5.1-Codex-Max - a $158.25 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
Based on overall model capabilities and architecture for coding tasks like generating functions, debugging, and refactoring
Customer support chatbot
Suitable for user-facing chat with competitive response times. Grok 4.1 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 (88/100) 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
GPT-5.1-Codex-Max has a moderate advantage with a 9.799999999999997-point lead in composite score. It wins on more signal dimensions, but Grok 4.1 Fast has specific strengths that could make it the better choice for certain workflows.
Best for Quality
GPT-5.1-Codex-Max
Marginally better benchmark scores; both are excellent
Best for Cost
Grok 4.1 Fast
94% lower pricing; better value at scale
Best for Reliability
GPT-5.1-Codex-Max
Higher uptime and faster response speeds
Best for Prototyping
GPT-5.1-Codex-Max
Stronger community support and better developer experience
Best for Production
GPT-5.1-Codex-Max
Wider enterprise adoption and proven at scale
by OpenAI
| Capability | GPT-5.1-Codex-Max | Grok 4.1 Fast |
|---|---|---|
| Vision (Image Input) | ||
| Function Calling | ||
| Streaming | ||
| JSON Mode | ||
| Reasoning | ||
| Web Search | ||
| Image Output |
OpenAI
xAI
Grok 4.1 Fast saves you $13.29/month
That's 93% cheaper than GPT-5.1-Codex-Max 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 | GPT-5.1-Codex-Max | Grok 4.1 Fast |
|---|---|---|
| Context Window | 400K | 2M |
| Max Output Tokens | 128,000 | 30,000 |
| Open Source | No | No |
| Created | Dec 4, 2025 | Nov 19, 2025 |
The premium pricing reflects Grok's 5x larger context window (2M vs 400K tokens) and its #1 ranking among 326 coding models, compared to GPT-5.1-Codex-Max's #15 position. For production codebases requiring extensive context retention across multiple files, Grok's 2M token window can eliminate costly context management overhead that would otherwise require multiple GPT-5.1 calls.
GPT-5.1-Codex-Max becomes more economical for outputs exceeding 30K tokens, where Grok would require multiple calls at $0.5/M output pricing. However, with a 61/100 score versus Grok's 75/100, you're trading a 23% quality gap for the ability to generate 4.3x longer outputs in a single call.
For typical coding tasks with 10:1 input/output ratios, GPT-5.1-Codex-Max costs $17.50 per million tokens processed versus Grok's $7 per million, making Grok 2.5x cheaper despite its higher output pricing. This advantage compounds in iterative development workflows where the same codebase context is repeatedly submitted.
While both support vision, function calling, and web search, Grok's file modality support and 2M token context enables processing entire repositories without chunking strategies. The 75/100 score likely reflects superior handling of multi-file dependencies and cross-reference accuracy that GPT-5.1-Codex-Max's 400K window struggles with at scale.
Migrating documentation workflows requires redesigning around Grok's 30K output limit, potentially splitting tasks that currently leverage GPT-5.1's 4.3x larger output capacity. However, the 75 vs 61 quality score suggests Grok's output may require less manual editing, potentially offsetting the need for multiple generation passes.