Model comparison
Claude Sonnet 5 vs Grok 4.1 Fast (Reasoning)
Head-to-head evidence from 10 shared benchmark results across 4 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Sonnet 5 #29 (Estimated); Grok 4.1 Fast (Reasoning) #48 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Sonnet 5 and Grok 4.1 Fast (Reasoning) share 10 comparable benchmark results. 0 of 8 categories are comparable. 26 results are unique to Claude Sonnet 5; 3 to Grok 4.1 Fast (Reasoning).
Updated July 23, 2026- Shared results
- 10
- Claude Sonnet 5 only
- 26
- Grok 4.1 Fast (Reasoning) only
- 3
- Comparable categories
- 0 / 8
Benchmark data for Claude Sonnet 5 and Grok 4.1 Fast (Reasoning) is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 10 shared benchmark results across 4 evidence categories; 0 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
BenchLM has partial data for these models, but not enough overlapping benchmark coverage to produce a fair score-level comparison yet.
Grok 4.1 Fast (Reasoning) has the larger context window at 2M, compared with 1M for Claude Sonnet 5.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | Claude Sonnet 5 | Δ | Grok 4.1 Fast (Reasoning) |
|---|---|---|---|
| Agentic | Claude Sonnet 581.9 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
| Coding | Claude Sonnet 576.7 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
| Knowledge | Claude Sonnet 557.4 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
| Multimodal | Claude Sonnet 588.3 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Sonnet 5 | Grok 4.1 Fast (Reasoning) | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Sonnet 5$2 input / $10 output | Grok 4.1 Fast (Reasoning)Not available | A complete price comparison is not available. |
| Generation speedtokens per second | Claude Sonnet 5Not available | Grok 4.1 Fast (Reasoning)Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Sonnet 5Not available | Grok 4.1 Fast (Reasoning)Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Sonnet 51M | Grok 4.1 Fast (Reasoning)2M | Grok 4.1 Fast (Reasoning) lists the larger context window. |
Benchmark Deep Dive
Agentic14 benchmarks
| Benchmark | Claude Sonnet 5 | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 80.4% | — | Not comparable |
| BrowseCompSource | 84.7% | — | Not comparable |
| HLE w/ toolsSource | 57.4% | — | Not comparable |
| OSWorld-VerifiedSource | 81.2% | — | Not comparable |
| GDPval-AASource | 1607 | — | Not comparable |
| AA Agentic IndexSource | 46.7% | — | Not comparable |
| GDPval-AASource | 55.4% | — | Not comparable |
| AA BriefcaseSource | 1388 | — | Not comparable |
| AA AutomationBenchSource | 39.2% | — | Not comparable |
| AA EnterpriseOps-GymSource | 44.7% | — | Not comparable |
| AA Harvey LABSource | 90.1% | — | Not comparable |
| AA Tau3 BankingSource | 28.2% | — | Not comparable |
| aaTerminalBench21Source | 80.5% | — | Not comparable |
| τ²-bench resultsSource | — | 93.3% | Not comparable |
Coding10 benchmarks
| Benchmark | Claude Sonnet 5 | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 85.2% | — | Not comparable |
| SWE-bench ProSource | 63.2% | — | Not comparable |
| SWE MultilingualSource | 78.3% | — | Not comparable |
| SWE MultimodalSource | 28.1% | — | Not comparable |
| Terminal-Bench 2.0Source | 80.4% | — | Not comparable |
| FrontierCode 1.1 MainSource | 42.7% | — | Not comparable |
| cursorBench32Source | 61.5% | — | Not comparable |
| AA Coding IndexSource | 71.5% | — | Not comparable |
| AA-SciCodeSource | 53.6% | 44.2% | Claude Sonnet 5 leads |
| Vibe Code BenchSource | — | 1.20% | Not comparable |
Reasoning2 benchmarks
Knowledge8 benchmarks
| Benchmark | Claude Sonnet 5 | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| HLESource | 57.4% | — | Not comparable |
| HLE w/o toolsSource | 43.2% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 53.4% | 30.6% | Claude Sonnet 5 leads |
| AA-GPQA DiamondSource | 91.1% | 85.3% | Claude Sonnet 5 leads |
| AA-HLESource | 39.6% | 17.6% | Claude Sonnet 5 leads |
| AA-Omniscience IndexSource | 15.3% | -28.7% | Claude Sonnet 5 leads |
| AA-Omniscience AccuracySource | 38.3% | 25.3% | Claude Sonnet 5 leads |
| AA-Omniscience Hallucination RateSource | 37.3% | 72.4% | Claude Sonnet 5 leads |
Multimodal4 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Sonnet 5 | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 52.7% | Not comparable |
Frequently Asked Questions (3)
Can I compare Claude Sonnet 5 and Grok 4.1 Fast (Reasoning) on BenchLM yet?
Not fully yet. BenchLM is tracking both models, but the sourced benchmark breakdown for this comparison is still coming soon.
Why does this comparison show “coming soon”?
BenchLM only shows category winners and benchmark-level calls when we have sourced results that can be compared fairly. For these models, the public benchmark coverage is not complete enough yet.
What data is available for Claude Sonnet 5 and Grok 4.1 Fast (Reasoning) today?
Claude Sonnet 5: $2.00 input / $10.00 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.
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