# GLM-5.3-Flash vs Grok 4.20

> Side-by-side benchmark comparison for GLM-5.3-Flash and Grok 4.20 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/glm-5-3-flash-vs-grok-4-20-beta
- Last updated: October 10, 2026

- Shared sourced benchmarks: 6
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

GLM-5.3-Flash leads by point estimate. Conditional score ranges do not establish rank confidence. Choose using the category evidence and your own workload tests.

## Summary

- GLM-5.3-Flash has the higher overall point estimate 57.36 to 57.33. Conditional score ranges do not establish rank confidence.
- The clearest category separation is in reasoning, where the averages are 81.1 for GLM-5.3-Flash and 44.9 for Grok 4.20.
- The biggest single benchmark swing is CharXiv in Multimodal & Grounded, with scores of 89.4% and 60.9%.
- GLM-5.3-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 | GLM-5.3-Flash | Grok 4.20 |
|----------|----------|----------|
| Creator | Z.AI | xAI |
| Type | Open Weight | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 2M |
| Overall Score | 57.36 | 57.33 |
| Benchmarks Covered | 21 | 23 |
| Pricing (input/output) | $0.00 / $0.00 | $1.25 / $2.50 |

## Category Breakdown

### Agentic

- Winner: GLM-5.3-Flash
- GLM-5.3-Flash public-lane score: 55.7 (Supported · #34/123)
- Grok 4.20 public-lane score: 24.4 (Supported · #98/123)

| Benchmark | GLM-5.3-Flash | Grok 4.20 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.1 | 84.3% | Coming soon | Coming soon |
| Toolathlon-Verified | 78.4% | Coming soon | Coming soon |
| AutomationBench | 48.8% | Coming soon | Coming soon |
| Agents' Last Exam | 26.3% | Coming soon | Coming soon |
| HLE w/ tools | 55.3% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 62.9% | 44.2% | GLM-5.3-Flash |
| Terminal-Bench 2.0 | Coming soon | 47.1% | Coming soon |
| DeepSearchQA | Coming soon | 62.8% | Coming soon |
| Gert Labs | Coming soon | 38.36% | Coming soon |

### Coding

- Winner: GLM-5.3-Flash
- GLM-5.3-Flash public-lane score: 49.3 (Supported · #42/146)
- Grok 4.20 public-lane score: 22.3 (Supported · #114/146)

| Benchmark | GLM-5.3-Flash | Grok 4.20 | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.1 | 84.3% | Coming soon | Coming soon |
| DeepSWE | 63.4% | Coming soon | Coming soon |
| NL2Repo | 56.3% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 80.5% | 84.3% | Grok 4.20 |
| SWE-bench (Vals) | 92.0% | 72.2% | GLM-5.3-Flash |
| OpenHarmony Bench | 57.3% | Coming soon | Coming soon |
| FrontierSWE v2 | 18.1% | Coming soon | Coming soon |
| Bug Hunt Bench | 17.7 fixes | Coming soon | Coming soon |
| LiveCodeBench Pro | Coming soon | 74.2% | Coming soon |
| SWE-bench Verified | Coming soon | 76.7% | Coming soon |
| SWE-bench Pro | Coming soon | 51.8% | Coming soon |
| Vibe Code Bench | Coming soon | 4.06% | Coming soon |

### Reasoning

- Winner: Not comparable
- GLM-5.3-Flash public-lane score: 81.1 (#11/28)
- Grok 4.20 public-lane score: 44.9 (Unranked · 2 rankable rows)

| Benchmark | GLM-5.3-Flash | Grok 4.20 | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-2 | Coming soon | 53.3% | Coming soon |
| ARC-AGI-3 | Coming soon | 0.1% | Coming soon |

### Multimodal & Grounded

- Winner: Directional only
- GLM-5.3-Flash public-lane score: 84 (#14/54)
- Grok 4.20 public-lane score: 53.4 (#47/54)

| Benchmark | GLM-5.3-Flash | Grok 4.20 | Winner |
|-----------|-----------|-----------|--------|
| OfficeQA Pro | 62.4% | Coming soon | Coming soon |
| CharXiv | 89.4% | 60.9% | GLM-5.3-Flash |
| Chartography (tools) | 78.0% | Coming soon | Coming soon |
| BabyVision | 53.4% | Coming soon | Coming soon |
| MMVU | 80.5% | Coming soon | Coming soon |
| MMMU-Pro | Coming soon | 75.2% | Coming soon |
| ERQA | Coming soon | 54.1% | Coming soon |
| SimpleVQA | Coming soon | 57.4% | Coming soon |
| MedXpertQA (MM) | Coming soon | 65.8% | Coming soon |

### Knowledge

- Winner: GLM-5.3-Flash
- GLM-5.3-Flash public-lane score: 60.5 (Supported · #43/177)
- Grok 4.20 public-lane score: 53.1 (Supported · #66/177)

| Benchmark | GLM-5.3-Flash | Grok 4.20 | Winner |
|-----------|-----------|-----------|--------|
| GPQA Diamond (Vals) | 86.4% | 88.6% | Grok 4.20 |
| MMLU-Pro (Vals) | 86.1% | 86.3% | Grok 4.20 |
| GPQA-D | Coming soon | 88.5% | Coming soon |
| HLE w/o tools | Coming soon | 31.6% | Coming soon |
| HealthBench Hard | Coming soon | 20.3% | Coming soon |
| MedXpertQA (Text) | Coming soon | 50.2% | Coming soon |

## FAQ

### Which is better overall, GLM-5.3-Flash or Grok 4.20?

GLM-5.3-Flash has the higher overall point estimate. Conditional score ranges do not establish rank confidence.

### Where is the biggest gap between GLM-5.3-Flash and Grok 4.20?

The widest category gap is in reasoning, where the averages are 81.1 for GLM-5.3-Flash and 44.9 for Grok 4.20.

### How many benchmarks does GLM-5.3-Flash cover on BenchLM?

GLM-5.3-Flash currently has 21 sourced benchmark scores on BenchLM.

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

Grok 4.20 currently has 23 sourced benchmark scores on BenchLM.

## Related Comparisons

- [GLM-5.3-Flash vs GLM-5.3](/compare/glm-5-3-vs-glm-5-3-flash)
- [Grok 4.20 vs GLM-5.3](/compare/glm-5-3-vs-grok-4-20-beta)
- [GLM-5.3-Flash vs GLM-5.2](/compare/glm-5-2-vs-glm-5-3-flash)
- [Grok 4.20 vs GLM-5.2](/compare/glm-5-2-vs-grok-4-20-beta)

## Explore More

- [GLM-5.3-Flash profile](/models/glm-5-3-flash)
- [Grok 4.20 profile](/models/grok-4-20-beta)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)