# Gemini 3.1 Flash-Lite vs Grok 4.20

> Side-by-side benchmark comparison for Gemini 3.1 Flash-Lite and Grok 4.20 across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/gemini-3-1-flash-lite-vs-grok-4-20-beta
- Last updated: September 10, 2026

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

## Quick Verdict

Pick Grok 4.20 if you want the stronger benchmark profile. Gemini 3.1 Flash-Lite 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 67.13 to 56.19.
- The clearest category separation is in agentic, where the averages are 42.9 for Gemini 3.1 Flash-Lite and 26.7 for Grok 4.20.
- The biggest single benchmark swing is CharXiv in Multimodal & Grounded, with scores of 73.2% and 60.9%.
- Gemini 3.1 Flash-Lite 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 | Gemini 3.1 Flash-Lite | Grok 4.20 |
|----------|----------|----------|
| Creator | Google | xAI |
| Type | Proprietary | Proprietary |
| Reasoning | Non-Reasoning | Reasoning |
| Context | 1M | 2M |
| Overall Score | 56.19 | 67.13 |
| Benchmarks Covered | 8 | 23 |
| Pricing (input/output) | $0.25 / $1.50 | $2.00 / $6.00 |

## Category Breakdown

### Agentic

- Winner: Coming soon
- Gemini 3.1 Flash-Lite public-lane score: 42.9 (Estimated · #101/152)
- Grok 4.20 public-lane score: 26.7 (Supported · #145/152)

| Benchmark | Gemini 3.1 Flash-Lite | Grok 4.20 | Winner |
|-----------|-----------|-----------|--------|
| Gert Labs | 38.46% | 38.36% | Gemini 3.1 Flash-Lite |
| Terminal-Bench 2.1 (Vals) | 34.1% | 44.2% | Grok 4.20 |
| Terminal-Bench 2.0 | Coming soon | 47.1% | Coming soon |
| DeepSearchQA | Coming soon | 62.8% | Coming soon |

### Coding

- Winner: Coming soon
- Gemini 3.1 Flash-Lite public-lane score: 37.9 (Estimated · #124/151)
- Grok 4.20 public-lane score: 28.2 (Supported · #141/151)

| Benchmark | Gemini 3.1 Flash-Lite | Grok 4.20 | Winner |
|-----------|-----------|-----------|--------|
| Vibe Code Bench | 0.00% | 4.06% | Grok 4.20 |
| LiveCodeBench (Vals) | 80.1% | 84.3% | Grok 4.20 |
| SWE-bench (Vals) | 62.8% | 72.2% | Grok 4.20 |
| 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 |

### Multimodal & Grounded

- Winner: Coming soon
- Gemini 3.1 Flash-Lite public-lane score: 37.5 (Unranked · 1 rankable row)
- Grok 4.20 public-lane score: 34.6 (#43/48)

| Benchmark | Gemini 3.1 Flash-Lite | Grok 4.20 | Winner |
|-----------|-----------|-----------|--------|
| CharXiv | 73.2% | 60.9% | Gemini 3.1 Flash-Lite |
| 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 |

### Reasoning

- Winner: Coming soon
- Gemini 3.1 Flash-Lite public-lane score: Coming soon
- Grok 4.20 public-lane score: 34.2 (Unranked · 2 rankable rows)

| Benchmark | Gemini 3.1 Flash-Lite | Grok 4.20 | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-2 | Coming soon | 53.3% | Coming soon |
| ARC-AGI-3 | Coming soon | 0.1% | Coming soon |

### Knowledge

- Winner: Coming soon
- Gemini 3.1 Flash-Lite public-lane score: 51.5 (Estimated · #71/183)
- Grok 4.20 public-lane score: 49.4 (Supported · #85/183)

| Benchmark | Gemini 3.1 Flash-Lite | Grok 4.20 | Winner |
|-----------|-----------|-----------|--------|
| GPQA Diamond (Vals) | 81.1% | 88.6% | Grok 4.20 |
| MMLU-Pro (Vals) | 86.2% | 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, Gemini 3.1 Flash-Lite or Grok 4.20?

Grok 4.20 is ahead overall on BenchLM right now.

### Where is the biggest gap between Gemini 3.1 Flash-Lite and Grok 4.20?

The widest category gap is in agentic, where the averages are 42.9 for Gemini 3.1 Flash-Lite and 26.7 for Grok 4.20.

### How many benchmarks does Gemini 3.1 Flash-Lite cover on BenchLM?

Gemini 3.1 Flash-Lite currently has 8 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

- [Gemini 3.1 Flash-Lite vs Grok 4.20 Multi-agent](/compare/gemini-3-1-flash-lite-vs-grok-4-20-multi-agent-beta)
- [Grok 4.20 vs Grok 4.20 Multi-agent](/compare/grok-4-20-beta-vs-grok-4-20-multi-agent-beta)
- [Gemini 3.1 Flash-Lite vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-gemini-3-1-flash-lite)
- [Grok 4.20 vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-grok-4-20-beta)

## Explore More

- [Gemini 3.1 Flash-Lite profile](/models/gemini-3-1-flash-lite)
- [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)