Model comparison
GPT-5.6 Sol vs Grok 4.1 Fast (Reasoning)
Head-to-head evidence from 12 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: GPT-5.6 Sol #3 (Supported); Grok 4.1 Fast (Reasoning) #48 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-5.6 Sol and Grok 4.1 Fast (Reasoning) share 12 comparable benchmark results. 0 of 8 categories are comparable. 34 results are unique to GPT-5.6 Sol; 1 to Grok 4.1 Fast (Reasoning).
Updated July 23, 2026- Shared results
- 12
- GPT-5.6 Sol only
- 34
- Grok 4.1 Fast (Reasoning) only
- 1
- Comparable categories
- 0 / 8
Benchmark data for GPT-5.6 Sol and Grok 4.1 Fast (Reasoning) is coming soon on BenchLM.
Confidence note. This is a partial-evidence comparison with 12 shared benchmark results across 6 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 GPT-5.6 Sol.
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 | GPT-5.6 Sol | Δ | Grok 4.1 Fast (Reasoning) |
|---|---|---|---|
| Agentic | GPT-5.6 Sol92.0 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
| Coding | GPT-5.6 Sol64.6 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
| Knowledge | GPT-5.6 Sol94.6 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
| Math | GPT-5.6 Sol87.5 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
| Multimodal | GPT-5.6 Sol83.0 | 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 | GPT-5.6 Sol | Grok 4.1 Fast (Reasoning) | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-5.6 Sol$5 input / $30 output | Grok 4.1 Fast (Reasoning)Not available | A complete price comparison is not available. |
| Generation speedtokens per second | GPT-5.6 SolNot available | Grok 4.1 Fast (Reasoning)Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GPT-5.6 SolNot available | Grok 4.1 Fast (Reasoning)Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GPT-5.6 Sol1M | Grok 4.1 Fast (Reasoning)2M | Grok 4.1 Fast (Reasoning) lists the larger context window. |
Benchmark Deep Dive
Agentic17 benchmarks
| Benchmark | GPT-5.6 Sol | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 91.9% | — | Not comparable |
| BrowseCompSource | 92.2% | — | Not comparable |
| OSWorld 2.0Source | 62.6% | — | Not comparable |
| CyberGymSource | 84.5% | — | Not comparable |
| ExploitGymSource | 33.7% | — | Not comparable |
| ToolathlonSource | 58% | — | Not comparable |
| AA Agentic IndexSource | 54.0% | — | Not comparable |
| τ²-bench resultsSource | 85.1% | 93.3% | Grok 4.1 Fast (Reasoning) leads |
| GDPval-AASource | 61.8% | — | Not comparable |
| GDPval-AASource | 1736 | — | Not comparable |
| AA BriefcaseSource | 1501 | — | Not comparable |
| AA ITBenchSource | 56.2% | — | Not comparable |
| AA Tau3 BankingSource | 33.0% | — | Not comparable |
| AA AutomationBenchSource | 51.2% | — | Not comparable |
| AA Harvey LABSource | 87.2% | — | Not comparable |
| terminalBenchHardSource | 65.9% | — | Not comparable |
| aaTerminalBench21Source | 88% | — | Not comparable |
Coding9 benchmarks
| Benchmark | GPT-5.6 Sol | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| SWE-bench ProSource | 64.6% | — | Not comparable |
| Terminal-Bench 2.0Source | 91.9% | — | Not comparable |
| deepSweSource | 72.7% | — | Not comparable |
| FrontierCode 1.1 ExtendedSource | 60.6% | — | Not comparable |
| cursorBench32Source | 67.2% | — | Not comparable |
| VulcanBench v3Source | 87.0% | — | Not comparable |
| AA Coding IndexSource | 77.4% | — | Not comparable |
| AA-SciCodeSource | 56.1% | 44.2% | GPT-5.6 Sol leads |
| Vibe Code BenchSource | — | 1.20% | Not comparable |
Reasoning4 benchmarks
Knowledge10 benchmarks
| Benchmark | GPT-5.6 Sol | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| GPQASource | 94.6% | — | Not comparable |
| GPQA-DSource | 94.6% | — | Not comparable |
| HealthBench ProfessionalSource | 60.5% | — | Not comparable |
| HealthBench HardSource | 33.1% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 58.9% | 30.6% | GPT-5.6 Sol leads |
| AA-GPQA DiamondSource | 94.1% | 85.3% | GPT-5.6 Sol leads |
| AA-HLESource | 47.2% | 17.6% | GPT-5.6 Sol leads |
| AA-Omniscience IndexSource | 21.7% | -28.7% | GPT-5.6 Sol leads |
| AA-Omniscience AccuracySource | 58.5% | 25.3% | GPT-5.6 Sol leads |
| AA-Omniscience Hallucination RateSource | 88.8% | 72.4% | Grok 4.1 Fast (Reasoning) leads |
Math3 benchmarks
Multimodal3 benchmarks
Inst. Following1 benchmarks
| Benchmark | GPT-5.6 Sol | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| AA-IFBenchSource | 72.7% | 52.7% | GPT-5.6 Sol leads |
Frequently Asked Questions (3)
Can I compare GPT-5.6 Sol 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 GPT-5.6 Sol and Grok 4.1 Fast (Reasoning) today?
GPT-5.6 Sol: $5.00 input / $30.00 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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