# Grok 4.20 vs Spark-X2.6-4B

> Side-by-side benchmark comparison for Grok 4.20 and Spark-X2.6-4B across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/grok-4-20-beta-vs-spark-x2-6-4b
- Last updated: October 20, 2026

- Shared sourced benchmarks: 4
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Grok 4.20 leads by point estimate. Conditional score ranges do not establish rank confidence. Choose using the category evidence and your own workload tests.

## Summary

- Grok 4.20 has the higher overall point estimate 57.41 to 40.14. Conditional score ranges do not establish rank confidence.
- The clearest category separation is in knowledge, where the averages are 53.2 for Grok 4.20 and 43 for Spark-X2.6-4B.
- The biggest single benchmark swing is SWE-bench Verified in Coding, with scores of 76.7% and 62.8%.
- Spark-X2.6-4B 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 | Spark-X2.6-4B |
|----------|----------|----------|
| Creator | xAI | SparkLLM |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Reasoning |
| Context | 2M | 1M |
| Overall Score | 57.41 | 40.14 |
| Benchmarks Covered | 24 | 20 |
| Pricing (input/output) | $1.25 / $2.50 | $0.00 / $0.00 |

## Category Breakdown

### Agentic

- Winner: Directional only
- Grok 4.20 public-lane score: 25.1 (Supported · #107/131)
- Spark-X2.6-4B public-lane score: 33 (Estimated · #89/131)

| Benchmark | Grok 4.20 | Spark-X2.6-4B | 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 |
| MazeBench | 0% | Coming soon | Coming soon |
| BFCL v4 | Coming soon | 71.8% | Coming soon |
| τ²-bench results | Coming soon | 86.9% | Coming soon |
| MCP Atlas | Coming soon | 62.4% | Coming soon |
| BrowseComp | Coming soon | 53.1% | Coming soon |
| HLE w/ tools | Coming soon | 36.9% | Coming soon |
| τ³-bench results | Coming soon | 34.7% | Coming soon |
| Claw-Eval | Coming soon | 69.9% | Coming soon |

### Coding

- Winner: Directional only
- Grok 4.20 public-lane score: 21.5 (Supported · #120/152)
- Spark-X2.6-4B public-lane score: 30.6 (Estimated · #95/152)

| Benchmark | Grok 4.20 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| LiveCodeBench Pro | 74.2% | Coming soon | Coming soon |
| SWE-bench Verified | 76.7% | 62.8% | Grok 4.20 |
| SWE-bench Pro | 51.8% | 54.3% | Spark-X2.6-4B |
| Vibe Code Bench | 4.06% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 84.3% | Coming soon | Coming soon |
| SWE-bench (Vals) | 72.2% | Coming soon | Coming soon |
| SWE Multilingual | Coming soon | 64.7% | Coming soon |
| SciCode | Coming soon | 36.8% | Coming soon |

### Reasoning

- Winner: Not comparable
- Grok 4.20 public-lane score: 44.9 (Unranked · 2 rankable rows)
- Spark-X2.6-4B public-lane score: 48.8 (Unranked · 2 rankable rows)

| Benchmark | Grok 4.20 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| ARC-AGI-2 | 53.3% | Coming soon | Coming soon |
| ARC-AGI-3 | 0.1% | Coming soon | Coming soon |
| LongBench v2 | Coming soon | 53.3% | Coming soon |

### Multimodal & Grounded

- Winner: Not comparable
- Grok 4.20 public-lane score: 53.4 (#48/55)
- Spark-X2.6-4B public-lane score: Coming soon

| Benchmark | Grok 4.20 | Spark-X2.6-4B | 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: 53.2 (Supported · #71/187)
- Spark-X2.6-4B public-lane score: 43 (Estimated · #109/187)

| Benchmark | Grok 4.20 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| GPQA-D | 88.5% | 77.1% | Grok 4.20 |
| HLE w/o tools | 31.6% | 17.9% | Grok 4.20 |
| HealthBench Hard | 20.3% | Coming soon | Coming soon |
| MedXpertQA (Text) | 50.2% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 88.6% | Coming soon | Coming soon |
| MMLU-Pro (Vals) | 86.3% | Coming soon | Coming soon |
| GPQA | Coming soon | 69.9% | Coming soon |

### Instruction Following

- Winner: Not comparable
- Grok 4.20 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 78.2 (#62/149)

| Benchmark | Grok 4.20 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| IFEval | Coming soon | 93.6% | Coming soon |
| IFBench | Coming soon | 75.8% | Coming soon |

### Mathematics

- Winner: Not comparable
- Grok 4.20 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 76.4 (Unranked · 3 rankable rows)

| Benchmark | Grok 4.20 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| AIME26 | Coming soon | 91.2% | Coming soon |
| HMMT Feb 2026 | Coming soon | 81.3% | Coming soon |
| IMOAnswerBench | Coming soon | 75.2% | Coming soon |

## FAQ

### Which is better overall, Grok 4.20 or Spark-X2.6-4B?

Grok 4.20 has the higher overall point estimate. Conditional score ranges do not establish rank confidence.

### Where is the biggest gap between Grok 4.20 and Spark-X2.6-4B?

The widest category gap is in knowledge, where the averages are 53.2 for Grok 4.20 and 43 for Spark-X2.6-4B.

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

Grok 4.20 currently has 24 sourced benchmark scores on BenchLM.

### How many benchmarks does Spark-X2.6-4B cover on BenchLM?

Spark-X2.6-4B currently has 20 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)
- [Spark-X2.6-4B vs Grok 4.20 Multi-agent](/compare/grok-4-20-multi-agent-beta-vs-spark-x2-6-4b)
- [Grok 4.20 vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-grok-4-20-beta)
- [Spark-X2.6-4B vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-spark-x2-6-4b)

## Explore More

- [Grok 4.20 profile](/models/grok-4-20-beta)
- [Spark-X2.6-4B profile](/models/spark-x2-6-4b)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)