# Grok 4.20 vs Qwen3.5 Flash

> Side-by-side benchmark comparison for Grok 4.20 and Qwen3.5 Flash across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/grok-4-20-beta-vs-qwen3-5-flash
- Last updated: September 29, 2026

- Shared sourced benchmarks: 4
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.7

## Quick Verdict

Pick Grok 4.20 if you want the stronger benchmark profile. Qwen3.5 Flash only makes more sense when its price, context window, or workload-specific category wins matter more than the overall score.

## Summary

- Grok 4.20 leads overall 59.74 to 45.47.
- The clearest category separation is in knowledge, where the averages are 49.2 for Grok 4.20 and 43.1 for Qwen3.5 Flash.
- The biggest single benchmark swing is SWE-bench (Vals) in Coding, with scores of 72.2% and 64.4%.
- Qwen3.5 Flash is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.
- Grok 4.20 also has the larger context window at 2M.

## Model Snapshot

| Property | Grok 4.20 | Qwen3.5 Flash |
|----------|----------|----------|
| Creator | xAI | Alibaba |
| Type | Proprietary | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 2M | 1M |
| Overall Score | 59.74 | 45.47 |
| Benchmarks Covered | 23 | 6 |
| Pricing (input/output) | $1.25 / $2.50 | $0.10 / $0.40 |

## Category Breakdown

### Agentic

- Winner: Not comparable
- Grok 4.20 public-lane score: 23.3 (Supported · #95/117)
- Qwen3.5 Flash public-lane score: Coming soon

| Benchmark | Grok 4.20 | Qwen3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 47.1% | Coming soon | Coming soon |
| DeepSearchQA | 62.8% | Coming soon | Coming soon |
| Gert Labs | 38.36% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 44.2% | Coming soon | Coming soon |

### Coding

- Winner: Directional only
- Grok 4.20 public-lane score: 22.5 (Supported · #115/143)
- Qwen3.5 Flash public-lane score: 26.5 (Estimated · #103/143)

| Benchmark | Grok 4.20 | Qwen3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| LiveCodeBench Pro | 74.2% | Coming soon | Coming soon |
| SWE-bench Verified | 76.7% | Coming soon | Coming soon |
| SWE-bench Pro | 51.8% | Coming soon | Coming soon |
| Vibe Code Bench | 4.06% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 84.3% | 83.3% | Grok 4.20 |
| SWE-bench (Vals) | 72.2% | 64.4% | Grok 4.20 |

### Reasoning

- Winner: Not comparable
- Grok 4.20 public-lane score: 41.1 (Unranked · 2 rankable rows)
- Qwen3.5 Flash public-lane score: Coming soon

| Benchmark | Grok 4.20 | Qwen3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-2 | 53.3% | Coming soon | Coming soon |
| ARC-AGI-3 | 0.1% | Coming soon | Coming soon |

### Multimodal & Grounded

- Winner: Not comparable
- Grok 4.20 public-lane score: 35.6 (#45/50)
- Qwen3.5 Flash public-lane score: Coming soon

| Benchmark | Grok 4.20 | Qwen3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| MMMU-Pro | 75.2% | Coming soon | Coming soon |
| CharXiv | 60.9% | Coming soon | Coming soon |
| ERQA | 54.1% | Coming soon | Coming soon |
| SimpleVQA | 57.4% | Coming soon | Coming soon |
| MedXpertQA (MM) | 65.8% | Coming soon | Coming soon |

### Knowledge

- Winner: Directional only
- Grok 4.20 public-lane score: 49.2 (Supported · #64/169)
- Qwen3.5 Flash public-lane score: 43.1 (Estimated · #85/169)

| Benchmark | Grok 4.20 | Qwen3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| GPQA-D | 88.5% | Coming soon | Coming soon |
| HLE w/o tools | 31.6% | Coming soon | Coming soon |
| HealthBench Hard | 20.3% | Coming soon | Coming soon |
| MedXpertQA (Text) | 50.2% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 88.6% | 82.8% | Grok 4.20 |
| MMLU-Pro (Vals) | 86.3% | 84.1% | Grok 4.20 |

### Mathematics

- Winner: Not comparable
- Grok 4.20 public-lane score: Coming soon
- Qwen3.5 Flash public-lane score: 28.4 (Unranked · 2 rankable rows)

| Benchmark | Grok 4.20 | Qwen3.5 Flash | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | Coming soon | 6.207% | Coming soon |
| FrontierMath v2 (Tier 4) | Coming soon | 0.000% | Coming soon |

## FAQ

### Which is better overall, Grok 4.20 or Qwen3.5 Flash?

Grok 4.20 is ahead overall on BenchLM right now.

### Where is the biggest gap between Grok 4.20 and Qwen3.5 Flash?

The widest category gap is in knowledge, where the averages are 49.2 for Grok 4.20 and 43.1 for Qwen3.5 Flash.

### How many benchmarks does Grok 4.20 cover on BenchLM?

Grok 4.20 currently has 23 sourced benchmark scores on BenchLM.

### How many benchmarks does Qwen3.5 Flash cover on BenchLM?

Qwen3.5 Flash currently has 6 sourced benchmark scores on BenchLM.

## Related Comparisons

- [Grok 4.20 vs Grok 4.20 Multi-agent](/compare/grok-4-20-beta-vs-grok-4-20-multi-agent-beta)
- [Qwen3.5 Flash vs Grok 4.20 Multi-agent](/compare/grok-4-20-multi-agent-beta-vs-qwen3-5-flash)
- [Grok 4.20 vs GPT-6 Astra](/compare/gpt-6-astra-vs-grok-4-20-beta)
- [Qwen3.5 Flash vs GPT-6 Astra](/compare/gpt-6-astra-vs-qwen3-5-flash)

## Explore More

- [Grok 4.20 profile](/models/grok-4-20-beta)
- [Qwen3.5 Flash profile](/models/qwen3-5-flash)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)