# LongCat-2.5 vs Spark-X2.6-4B

> Side-by-side benchmark comparison for LongCat-2.5 and Spark-X2.6-4B across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/longcat-2-5-vs-spark-x2-6-4b
- Last updated: November 9, 2026

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

## Quick Verdict

Spark-X2.6-4B leads by point estimate. Conditional score ranges do not establish rank confidence. Choose using the category evidence and your own workload tests.

## Summary

- Spark-X2.6-4B has the higher overall point estimate 40.35 to 0. Conditional score ranges do not establish rank confidence.
- The biggest single benchmark swing is BrowseComp in Agentic, with scores of 91.9% 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 | LongCat-2.5 | Spark-X2.6-4B |
|----------|----------|----------|
| Creator | Meituan | SparkLLM |
| Type | Open Weight | Open Weight |
| Reasoning | Hybrid | Reasoning |
| Context | 1M | 1M |
| Overall Score | null | 40.35 |
| Benchmarks Covered | 22 | 20 |
| Pricing (input/output) | $0.30 / $1.20 | $0.00 / $0.00 |

## Category Breakdown

### Agentic

- Winner: Not comparable
- LongCat-2.5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 35.8 (Estimated · #85/132)

| Benchmark | LongCat-2.5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.1 | 88.4% | Coming soon | Coming soon |
| Terminal-Bench 4.0 | 38.50% | Coming soon | Coming soon |
| BrowseComp | 91.9% | 53.1% | LongCat-2.5 |
| AutomationBench | 51.8% | Coming soon | Coming soon |
| HLE w/ tools | 63.1% | 36.9% | LongCat-2.5 |
| Agents' Last Exam | 38.5% | Coming soon | Coming soon |
| MCP Atlas | 83.1% | 62.4% | LongCat-2.5 |
| JobBench | 65.4% | Coming soon | Coming soon |
| skillsBench | 63.3% | Coming soon | Coming soon |
| SpreadsheetBench 2 | 34.9% | Coming soon | Coming soon |
| Claw-Eval | 78.3% | 69.9% | LongCat-2.5 |
| BFCL v4 | Coming soon | 71.8% | Coming soon |
| τ²-bench results | Coming soon | 86.9% | Coming soon |
| τ³-bench results | Coming soon | 34.7% | Coming soon |

### Coding

- Winner: Not comparable
- LongCat-2.5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 33.4 (Estimated · #97/158)

| Benchmark | LongCat-2.5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.1 | 88.4% | Coming soon | Coming soon |
| ProgramBench | 25.5% | Coming soon | Coming soon |
| DeepSWE | 64.6% | Coming soon | Coming soon |
| PaperBench | 82.1% | Coming soon | Coming soon |
| SWE-Atlas Codebase QnA | 58.3% | Coming soon | Coming soon |
| NL2Repo | 60.5% | Coming soon | Coming soon |
| SWE-bench Pro | Coming soon | 54.3% | Coming soon |
| SWE-bench Verified | Coming soon | 62.8% | Coming soon |
| SWE Multilingual | Coming soon | 64.7% | Coming soon |
| SciCode | Coming soon | 36.8% | Coming soon |

### Reasoning

- Winner: Not comparable
- LongCat-2.5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: Coming soon

| Benchmark | LongCat-2.5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| LongBench v2 | Coming soon | 53.3% | Coming soon |

### Multimodal & Grounded

- Winner: Not comparable
- LongCat-2.5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: Coming soon

| Benchmark | LongCat-2.5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| Vision2Web | 78.6% | Coming soon | Coming soon |
| CharXiv | 90.2% | Coming soon | Coming soon |
| MathVision w/ Python | 96.5% | Coming soon | Coming soon |
| Video-MME | 85.2% | Coming soon | Coming soon |

### Knowledge

- Winner: Not comparable
- LongCat-2.5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 43 (Estimated · #105/179)

| Benchmark | LongCat-2.5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| FrontierScience | 77% | Coming soon | Coming soon |
| GPQA-D | Coming soon | 77.1% | Coming soon |
| HLE w/o tools | Coming soon | 17.9% | Coming soon |
| GPQA | Coming soon | 69.9% | Coming soon |

### Instruction Following

- Winner: Not comparable
- LongCat-2.5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 78.2 (#66/157)

| Benchmark | LongCat-2.5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| IFEval | Coming soon | 93.6% | Coming soon |
| IFBench | Coming soon | 75.8% | Coming soon |

### Mathematics

- Winner: Not comparable
- LongCat-2.5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 60.9 (Unranked · 3 rankable rows)

| Benchmark | LongCat-2.5 | 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, LongCat-2.5 or Spark-X2.6-4B?

Spark-X2.6-4B has the higher overall point estimate. Conditional score ranges do not establish rank confidence.

### How many benchmarks does LongCat-2.5 cover on BenchLM?

LongCat-2.5 currently has 22 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

- [LongCat-2.5 vs Claude Fable 5.2](/compare/claude-fable-5-2-vs-longcat-2-5)
- [Spark-X2.6-4B vs Claude Fable 5.2](/compare/claude-fable-5-2-vs-spark-x2-6-4b)
- [LongCat-2.5 vs Gemini 4 Carbon](/compare/gemini-4-carbon-vs-longcat-2-5)
- [Spark-X2.6-4B vs Gemini 4 Carbon](/compare/gemini-4-carbon-vs-spark-x2-6-4b)

## Explore More

- [LongCat-2.5 profile](/models/longcat-2-5)
- [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)