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

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

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

- Shared sourced benchmarks: 5
- HTML indexing: indexable
- Ranking lane: BenchAlign v5.8

## Quick Verdict

Claude Mythos 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 Mythos 5 has the higher overall point estimate 85 to 40.14. Conditional score ranges do not establish rank confidence.
- The biggest single benchmark swing is HLE w/o tools in Knowledge, with scores of 59% and 17.9%.
- 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 Mythos 5 | Spark-X2.6-4B |
|----------|----------|----------|
| Creator | Anthropic | SparkLLM |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Reasoning |
| Context | 1M+ | 1M |
| Overall Score | null | 40.14 |
| Benchmarks Covered | 15 | 20 |
| Pricing (input/output) | $10.00 / $50.00 | $0.00 / $0.00 |

## Category Breakdown

### Agentic

- Winner: Not comparable
- Claude Mythos 5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 33 (Estimated · #89/131)

| Benchmark | Claude Mythos 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.1 | 88.0% | Coming soon | Coming soon |
| OSWorld-Verified | 85% | Coming soon | Coming soon |
| BrowseComp | 88% | 53.1% | Claude Mythos 5 |
| CyberGym | 83.8% | 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 |
| 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: Not comparable
- Claude Mythos 5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 30.6 (Estimated · #95/152)

| Benchmark | Claude Mythos 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 95.5% | 62.8% | Claude Mythos 5 |
| SWE-bench Pro | 80.3% | 54.3% | Claude Mythos 5 |
| Terminal-Bench 2.1 | 88.0% | Coming soon | Coming soon |
| SWE Multilingual | Coming soon | 64.7% | Coming soon |
| SciCode | Coming soon | 36.8% | Coming soon |

### Reasoning

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

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

### Multimodal & Grounded

- Winner: Not comparable
- Claude Mythos 5 public-lane score: 89.7 (Unranked · 3 rankable rows)
- Spark-X2.6-4B public-lane score: Coming soon

| Benchmark | Claude Mythos 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Multimodal | 54.9% | Coming soon | Coming soon |
| CharXiv | 93.5% | Coming soon | Coming soon |
| CharXiv w/o tools | 88.9% | Coming soon | Coming soon |

### Knowledge

- Winner: Not comparable
- Claude Mythos 5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 43 (Estimated · #109/187)

| Benchmark | Claude Mythos 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 94.1% | 69.9% | Claude Mythos 5 |
| HLE | 64.5% | Coming soon | Coming soon |
| HLE w/o tools | 59% | 17.9% | Claude Mythos 5 |
| GPQA-D | Coming soon | 77.1% | Coming soon |

### Multilingual

- Winner: Not comparable
- Claude Mythos 5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: Coming soon

| Benchmark | Claude Mythos 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| SWE Multilingual | 92.2% | Coming soon | Coming soon |

### Instruction Following

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

| Benchmark | Claude Mythos 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 Mythos 5 public-lane score: Coming soon
- Spark-X2.6-4B public-lane score: 76.4 (Unranked · 3 rankable rows)

| Benchmark | Claude Mythos 5 | Spark-X2.6-4B | Winner |
|-----------|-----------|-----------|--------|
| USAMO 2026 | 97.6% | 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 Mythos 5 or Spark-X2.6-4B?

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

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

Claude Mythos 5 currently has 15 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 Mythos 5 vs Claude Mythos 5.1](/compare/claude-mythos-5-vs-claude-mythos-5-1)
- [Spark-X2.6-4B vs Claude Mythos 5.1](/compare/claude-mythos-5-1-vs-spark-x2-6-4b)
- [Claude Mythos 5 vs Claude Mythos Preview](/compare/claude-mythos-5-vs-claude-mythos-preview)
- [Spark-X2.6-4B vs Claude Mythos Preview](/compare/claude-mythos-preview-vs-spark-x2-6-4b)

## Explore More

- [Claude Mythos 5 profile](/models/claude-mythos-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)