# GLM-5.1 vs Grok 4.1 Fast (Reasoning)

> Side-by-side benchmark comparison for GLM-5.1 and Grok 4.1 Fast (Reasoning) across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/glm-5-1-vs-grok-4-1-fast-reasoning
- Last updated: September 4, 2026

- Shared sourced benchmarks: 1
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Evidence is too thin for a benchmark verdict: GLM-5.1 and Grok 4.1 Fast (Reasoning) share only 1 sourced benchmark row.

## Summary

- Only 1 shared sourced benchmark row is available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- Grok 4.1 Fast (Reasoning) has the larger published context window at 2M.

## Model Snapshot

| Property | GLM-5.1 | Grok 4.1 Fast (Reasoning) |
|----------|----------|----------|
| Creator | Z.AI | xAI |
| Type | Open Weight | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 203K | 2M |
| Independent public score (not head-to-head) | 64.41 | 58.18 |
| Benchmarks Covered | 26 | 1 |
| Pricing (input/output) | $1.40 / $4.40 | N/A |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- GLM-5.1 public-lane score: 50.1 (Estimated · #63/151)
- Grok 4.1 Fast (Reasoning) public-lane score: Coming soon

| Benchmark | GLM-5.1 | Grok 4.1 Fast (Reasoning) | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 63.5% | Coming soon | Coming soon |
| BrowseComp | 68% | Coming soon | Coming soon |
| τ³-bench results | 70.6% | Coming soon | Coming soon |
| MCP Atlas | 71.8% | Coming soon | Coming soon |
| CyberGym | 68.7% | Coming soon | Coming soon |
| Claw-Eval | 62.3% | Coming soon | Coming soon |
| Gert Labs | 60.11% | Coming soon | Coming soon |
| ResearchClawBench | 18.2% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 56.9% | Coming soon | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- GLM-5.1 public-lane score: 56.8 (Supported · #39/183)
- Grok 4.1 Fast (Reasoning) public-lane score: 48.7 (Estimated · #85/183)

| Benchmark | GLM-5.1 | Grok 4.1 Fast (Reasoning) | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Pro | 58.4% | Coming soon | Coming soon |
| NL2Repo | 42.7% | Coming soon | Coming soon |
| SWE-Rebench | 62.7% | Coming soon | Coming soon |
| Vibe Code Bench | 31.46% | 1.20% | GLM-5.1 |
| OpenHarmony Bench | 52.3% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 81.4% | Coming soon | Coming soon |
| SWE-bench (Vals) | 76.4% | Coming soon | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- GLM-5.1 public-lane score: Coming soon
- Grok 4.1 Fast (Reasoning) public-lane score: 53.3 (Unranked · 1 rankable row)

### Reasoning

- Winner: Insufficient shared evidence
- GLM-5.1 public-lane score: 69.9 (Unranked · 2 rankable rows)
- Grok 4.1 Fast (Reasoning) public-lane score: 71.6 (Unranked · 2 rankable rows)

### Knowledge

- Winner: Insufficient shared evidence
- GLM-5.1 public-lane score: 55.4 (Supported · #59/181)
- Grok 4.1 Fast (Reasoning) public-lane score: 51.5 (Estimated · #82/181)

| Benchmark | GLM-5.1 | Grok 4.1 Fast (Reasoning) | Winner |
|-----------|-----------|-----------|--------|
| GPQA-D | 86.2% | Coming soon | Coming soon |
| HLE | 52.3% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 84.5% | Coming soon | Coming soon |
| MMLU-Pro (Vals) | 86.9% | Coming soon | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- GLM-5.1 public-lane score: 93.5 (#5/120)
- Grok 4.1 Fast (Reasoning) public-lane score: 62.8 (#69/120)

### Mathematics

- Winner: Insufficient shared evidence
- GLM-5.1 public-lane score: 64.1 (#3/7)
- Grok 4.1 Fast (Reasoning) public-lane score: Coming soon

| Benchmark | GLM-5.1 | Grok 4.1 Fast (Reasoning) | Winner |
|-----------|-----------|-----------|--------|
| AIME26 | 95.3% | Coming soon | Coming soon |
| HMMT Nov 2025 | 94.0% | Coming soon | Coming soon |
| HMMT Feb 2026 | 82.6% | Coming soon | Coming soon |
| MMAnswerBench | 83.8% | Coming soon | Coming soon |
| FrontierMath v2 (Tiers 1-3) | 33.448% | Coming soon | Coming soon |
| FrontierMath v2 (Tier 4) | 12.500% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between GLM-5.1 and Grok 4.1 Fast (Reasoning)?

Not yet. The models share only 1 sourced benchmark row, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [GLM-5.1 vs GLM-5.3](/compare/glm-5-1-vs-glm-5-3)
- [Grok 4.1 Fast (Reasoning) vs GLM-5.3](/compare/glm-5-3-vs-grok-4-1-fast-reasoning)
- [GLM-5.1 vs GLM-5.2](/compare/glm-5-1-vs-glm-5-2)
- [Grok 4.1 Fast (Reasoning) vs GLM-5.2](/compare/glm-5-2-vs-grok-4-1-fast-reasoning)

## Explore More

- [GLM-5.1 profile](/models/glm-5-1)
- [Grok 4.1 Fast (Reasoning) profile](/models/grok-4-1-fast-reasoning)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)