# Claude Sonnet 5 vs Spark-X2.6-4B

> Side-by-side benchmark comparison for Claude Sonnet 5 and Spark-X2.6-4B across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-sonnet-5-vs-spark-x2-6-4b
- Last updated: October 20, 2026

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

## Quick Verdict

Claude Sonnet 5 leads by point estimate. Conditional score ranges do not establish rank confidence. Choose using the category evidence and your own workload tests.

## Summary

- Claude Sonnet 5 has the higher overall point estimate 64.87 to 40.14. Conditional score ranges do not establish rank confidence.
- The clearest category separation is in agentic, where the averages are 66.3 for Claude Sonnet 5 and 33 for Spark-X2.6-4B.
- The biggest single benchmark swing is BrowseComp in Agentic, with scores of 84.7% and 53.1%.
- Spark-X2.6-4B is the cheaper option on output tokens, which matters if you expect large responses or heavy interactive use.

## Model Snapshot

| Property | Claude Sonnet 5 | Spark-X2.6-4B |
|----------|----------|----------|
| Creator | Anthropic | SparkLLM |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Reasoning |
| Context | 1M | 1M |
| Overall Score | 64.87 | 40.14 |
| Benchmarks Covered | 30 | 20 |
| Pricing (input/output) | $2.00 / $10.00 | $0.00 / $0.00 |

## Category Breakdown

### Agentic

- Winner: Directional only
- Claude Sonnet 5 public-lane score: 66.3 (Supported · #15/131)
- Spark-X2.6-4B public-lane score: 33 (Estimated · #89/131)

| Benchmark | Claude Sonnet 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 3.0 | 14.6% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | 80.4% | Coming soon | Coming soon |
| BrowseComp | 84.7% | 53.1% | Claude Sonnet 5 |
| HLE w/ tools | 57.4% | 36.9% | Claude Sonnet 5 |
| OSWorld-Verified | 81.2% | Coming soon | Coming soon |
| Terminal-Bench 2.1 (Vals) | 74.5% | Coming soon | Coming soon |
| ApprenticeBench | 16% | 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 |
| τ³-bench results | Coming soon | 34.7% | Coming soon |
| Claw-Eval | Coming soon | 69.9% | Coming soon |

### Coding

- Winner: Directional only
- Claude Sonnet 5 public-lane score: 57.5 (Supported · #26/152)
- Spark-X2.6-4B public-lane score: 30.6 (Estimated · #95/152)

| Benchmark | Claude Sonnet 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 85.2% | 62.8% | Claude Sonnet 5 |
| SWE-bench Pro | 63.2% | 54.3% | Claude Sonnet 5 |
| SWE Multilingual | 78.3% | 64.7% | Claude Sonnet 5 |
| SWE Multimodal | 28.1% | Coming soon | Coming soon |
| Terminal-Bench 2.1 | 80.4% | Coming soon | Coming soon |
| FrontierCode 1.1 Main | 42.7% | Coming soon | Coming soon |
| CursorBench 3.2 | 61.5% | Coming soon | Coming soon |
| VulcanBench CII v1 | 89.2% | Coming soon | Coming soon |
| LiveCodeBench (Vals) | 82.4% | Coming soon | Coming soon |
| SWE-bench (Vals) | 79.6% | Coming soon | Coming soon |
| CursorBench 4.0 | 34.1% | Coming soon | Coming soon |
| SciCode | Coming soon | 36.8% | Coming soon |

### Reasoning

- Winner: Not comparable
- Claude Sonnet 5 public-lane score: 81.3 (Unranked · 2 rankable rows)
- Spark-X2.6-4B public-lane score: 48.8 (Unranked · 2 rankable rows)

| Benchmark | Claude Sonnet 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| LongBench v2 | Coming soon | 53.3% | Coming soon |

### Multimodal & Grounded

- Winner: Not comparable
- Claude Sonnet 5 public-lane score: 82 (#15/55)
- Spark-X2.6-4B public-lane score: Coming soon

| Benchmark | Claude Sonnet 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| ParseBench | 62.13% | Coming soon | Coming soon |
| CharXiv | 88.3% | Coming soon | Coming soon |
| CharXiv w/o tools | 77% | Coming soon | Coming soon |

### Knowledge

- Winner: Directional only
- Claude Sonnet 5 public-lane score: 65.4 (Supported · #34/187)
- Spark-X2.6-4B public-lane score: 43 (Estimated · #109/187)

| Benchmark | Claude Sonnet 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| HLE | 57.4% | Coming soon | Coming soon |
| HLE w/o tools | 43.2% | 17.9% | Claude Sonnet 5 |
| HLE-Verified | 31.0% | Coming soon | Coming soon |
| LABBench2 | 80.1% | Coming soon | Coming soon |
| GPQA Diamond (Vals) | 88.9% | Coming soon | Coming soon |
| MMLU-Pro (Vals) | 87.5% | Coming soon | Coming soon |
| GPQA-D | Coming soon | 77.1% | Coming soon |
| GPQA | Coming soon | 69.9% | Coming soon |

### Instruction Following

- Winner: Not comparable
- Claude Sonnet 5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 78.2 (#62/149)

| Benchmark | Claude Sonnet 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| IFEval | Coming soon | 93.6% | Coming soon |
| IFBench | Coming soon | 75.8% | Coming soon |

### Mathematics

- Winner: Not comparable
- Claude Sonnet 5 public-lane score: 69.4 (Unranked · 2 rankable rows)
- Spark-X2.6-4B public-lane score: 76.4 (Unranked · 3 rankable rows)

| Benchmark | Claude Sonnet 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath v2 (Tiers 1-3) | 65.614% | Coming soon | Coming soon |
| FrontierMath v2 (Tier 4) | 29.268% | Coming soon | Coming soon |
| 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, Claude Sonnet 5 or Spark-X2.6-4B?

Claude Sonnet 5 has the higher overall point estimate. Conditional score ranges do not establish rank confidence.

### Where is the biggest gap between Claude Sonnet 5 and Spark-X2.6-4B?

The widest category gap is in agentic, where the averages are 66.3 for Claude Sonnet 5 and 33 for Spark-X2.6-4B.

### How many benchmarks does Claude Sonnet 5 cover on BenchLM?

Claude Sonnet 5 currently has 30 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

- [Claude Sonnet 5 vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-claude-sonnet-5)
- [Spark-X2.6-4B vs Claude Opus 5.5](/compare/claude-opus-5-5-vs-spark-x2-6-4b)
- [Claude Sonnet 5 vs GPT-6.1 Sol](/compare/claude-sonnet-5-vs-gpt-6-1-sol)
- [Spark-X2.6-4B vs GPT-6.1 Sol](/compare/gpt-6-1-sol-vs-spark-x2-6-4b)

## Explore More

- [Claude Sonnet 5 profile](/models/claude-sonnet-5)
- [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)