Model comparison
GLM-5.1 vs Grok 4.1 Fast (Reasoning)
Head-to-head evidence from 12 shared benchmark results across 5 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: GLM-5.1 #18 (Supported); Grok 4.1 Fast (Reasoning) #48 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GLM-5.1 and Grok 4.1 Fast (Reasoning) share 12 comparable benchmark results. 0 of 8 categories are comparable. 24 results are unique to GLM-5.1; 1 to Grok 4.1 Fast (Reasoning).
Updated July 23, 2026- Shared results
- 12
- GLM-5.1 only
- 24
- Grok 4.1 Fast (Reasoning) only
- 1
- Comparable categories
- 0 / 8
Benchmark data for GLM-5.1 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 5 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 203K for GLM-5.1.
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 | GLM-5.1 | Δ | Grok 4.1 Fast (Reasoning) |
|---|---|---|---|
| Agentic | GLM-5.165.4 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
| Coding | GLM-5.161.3 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
| Knowledge | GLM-5.152.3 | MarginNo overlap | Grok 4.1 Fast (Reasoning)Not measured |
| Math | GLM-5.162.0 | 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 | GLM-5.1 | Grok 4.1 Fast (Reasoning) | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GLM-5.1$1.4 input / $4.4 output | Grok 4.1 Fast (Reasoning)Not available | A complete price comparison is not available. |
| Generation speedtokens per second | GLM-5.1Not available | Grok 4.1 Fast (Reasoning)Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GLM-5.1Not available | Grok 4.1 Fast (Reasoning)Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GLM-5.1203K | Grok 4.1 Fast (Reasoning)2M | Grok 4.1 Fast (Reasoning) lists the larger context window. |
Benchmark Deep Dive
Agentic12 benchmarks
| Benchmark | GLM-5.1 | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 63.5% | — | Not comparable |
| BrowseCompSource | 68% | — | Not comparable |
| τ³-bench resultsSource | 70.6% | — | Not comparable |
| MCP AtlasSource | 71.8% | — | Not comparable |
| CyberGymSource | 68.7% | — | Not comparable |
| Claw-EvalSource | 62.3% | — | Not comparable |
| AA Agentic IndexSource | 29.9% | — | Not comparable |
| τ²-bench resultsSource | 97.7% | 93.3% | GLM-5.1 leads |
| GDPval-AASource | 37.8% | — | Not comparable |
| Gert LabsSource | 60.11% | — | Not comparable |
| GDPval-AASource | 1257 | — | Not comparable |
| ResearchClawBenchSource | 18.2% | — | Not comparable |
Coding6 benchmarks
| Benchmark | GLM-5.1 | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| SWE-bench ProSource | 58.4% | — | Not comparable |
| NL2RepoSource | 42.7% | — | Not comparable |
| SWE-RebenchSource | 62.7% | — | Not comparable |
| Vibe Code BenchSource | 31.46% | 1.20% | GLM-5.1 leads |
| AA Coding IndexSource | 55.8% | — | Not comparable |
| AA-SciCodeSource | 43.8% | 44.2% | Grok 4.1 Fast (Reasoning) leads |
Reasoning2 benchmarks
Knowledge8 benchmarks
| Benchmark | GLM-5.1 | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| GPQA-DSource | 86.2% | — | Not comparable |
| HLESource | 52.3% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 40.2% | 30.6% | GLM-5.1 leads |
| AA-GPQA DiamondSource | 86.8% | 85.3% | GLM-5.1 leads |
| AA-HLESource | 28.0% | 17.6% | GLM-5.1 leads |
| AA-Omniscience IndexSource | 1.9% | -28.7% | GLM-5.1 leads |
| AA-Omniscience AccuracySource | 24.2% | 25.3% | Grok 4.1 Fast (Reasoning) leads |
| AA-Omniscience Hallucination RateSource | 29.4% | 72.4% | GLM-5.1 leads |
Math6 benchmarks
| Benchmark | GLM-5.1 | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| AIME26Source | 95.3% | — | Not comparable |
| HMMT Nov 2025Source | 94.0% | — | Not comparable |
| HMMT Feb 2026Source | 82.6% | — | Not comparable |
| MMAnswerBenchSource | 83.8% | — | Not comparable |
| FrontierMath v2 (Tiers 1-3)Source | 33.448% | — | Not comparable |
| FrontierMath v2 (Tier 4)Source | 12.500% | — | Not comparable |
Multimodal2 benchmarks
Inst. Following1 benchmarks
| Benchmark | GLM-5.1 | Grok 4.1 Fast (Reasoning) | Result |
|---|---|---|---|
| AA-IFBenchSource | 76.3% | 52.7% | GLM-5.1 leads |
Frequently Asked Questions (3)
Can I compare GLM-5.1 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 GLM-5.1 and Grok 4.1 Fast (Reasoning) today?
GLM-5.1: $1.40 input / $4.40 output per 1M tokens Both model pages still include creator, context window, reasoning mode, and other metadata while benchmark coverage fills in.
Self-host vs API cost
Estimates at 50,000 req/day · 1000 tokens/req average.
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