# Mellum2-12B-A2.5B-Thinking vs Qwen3.8-Omni-Flash

> Side-by-side benchmark comparison for Mellum2-12B-A2.5B-Thinking and Qwen3.8-Omni-Flash across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/mellum2-12b-a2-5b-thinking-vs-qwen3-8-omni-flash
- Last updated: September 18, 2026

- Shared sourced benchmarks: 3
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Evidence is too thin for a benchmark verdict: Mellum2-12B-A2.5B-Thinking and Qwen3.8-Omni-Flash share only 3 sourced benchmark rows.

## Summary

- Only 3 shared sourced benchmark rows are available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- Qwen3.8-Omni-Flash has the larger published context window at 1M.

## Model Snapshot

| Property | Mellum2-12B-A2.5B-Thinking | Qwen3.8-Omni-Flash |
|----------|----------|----------|
| Creator | JetBrains | Alibaba |
| Type | Open Weight | Proprietary |
| Reasoning | Reasoning | Reasoning |
| Context | 128K | 1M |
| Independent public score (not head-to-head) | null | null |
| Benchmarks Covered | 6 | 19 |
| Pricing (input/output) | N/A | Pricing unavailable / Pricing unavailable |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Mellum2-12B-A2.5B-Thinking public-lane score: 46.3 (Estimated · #81/154)
- Qwen3.8-Omni-Flash public-lane score: Coming soon

| Benchmark | Mellum2-12B-A2.5B-Thinking | Qwen3.8-Omni-Flash | Winner |
|-----------|-----------|-----------|--------|
| BFCL v4 | 45.6% | Coming soon | Coming soon |
| CoWorkBench | Coming soon | 75.3% | Coming soon |
| AndroidWorld | Coming soon | 87.1% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Mellum2-12B-A2.5B-Thinking public-lane score: Coming soon
- Qwen3.8-Omni-Flash public-lane score: 53.5 (Estimated · #45/154)

| Benchmark | Mellum2-12B-A2.5B-Thinking | Qwen3.8-Omni-Flash | Winner |
|-----------|-----------|-----------|--------|
| LiveCodeBench v6 | 69.9% | 92.6% | Qwen3.8-Omni-Flash |
| SWE-bench Pro | Coming soon | 63.3% | Coming soon |
| SWE Multilingual | Coming soon | 80.5% | Coming soon |
| NL2Repo | Coming soon | 48.9% | Coming soon |
| DeepSWE | Coming soon | 57.8% | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- Mellum2-12B-A2.5B-Thinking public-lane score: Coming soon
- Qwen3.8-Omni-Flash public-lane score: 85.1 (Unranked · 7 rankable rows)

| Benchmark | Mellum2-12B-A2.5B-Thinking | Qwen3.8-Omni-Flash | Winner |
|-----------|-----------|-----------|--------|
| Vision2Web | Coming soon | 62.9% | Coming soon |
| ERQA | Coming soon | 71.0% | Coming soon |
| LVBench | Coming soon | 76.9% | Coming soon |
| RealWorldQA | Coming soon | 87.7% | Coming soon |
| MathVision | Coming soon | 91.8% | Coming soon |
| MathVision w/ Python | Coming soon | 96.2% | Coming soon |
| CharXiv w/o tools | Coming soon | 83.5% | Coming soon |
| CharXiv | Coming soon | 91.4% | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- Mellum2-12B-A2.5B-Thinking public-lane score: 46.8 (Estimated · #103/184)
- Qwen3.8-Omni-Flash public-lane score: 54.9 (Estimated · #54/184)

| Benchmark | Mellum2-12B-A2.5B-Thinking | Qwen3.8-Omni-Flash | Winner |
|-----------|-----------|-----------|--------|
| MMLU-Redux | 86.2% | Coming soon | Coming soon |
| GPQA | 57.6% | 91% | Qwen3.8-Omni-Flash |
| GPQA-D | 57.6% | 91.0% | Qwen3.8-Omni-Flash |
| HLE | Coming soon | 36.5% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Mellum2-12B-A2.5B-Thinking public-lane score: Coming soon
- Qwen3.8-Omni-Flash public-lane score: 87.7 (#29/124)

| Benchmark | Mellum2-12B-A2.5B-Thinking | Qwen3.8-Omni-Flash | Winner |
|-----------|-----------|-----------|--------|
| IFEval | 76.5% | Coming soon | Coming soon |
| IFBench | Coming soon | 81.5% | Coming soon |

## FAQ

### Is there enough evidence to pick between Mellum2-12B-A2.5B-Thinking and Qwen3.8-Omni-Flash?

Not yet. The models share only 3 sourced benchmark rows, so this mirror reports the available measurements and metadata without naming a broad winner.

### What can I compare safely on this page?

Published pricing, context windows, model type, and individual shared benchmark rows are directly comparable. Independent overall scores and non-overlapping benchmark coverage are labeled separately and should not be read as a controlled head-to-head result.

## Related Comparisons

- [Mellum2-12B-A2.5B-Thinking vs Mellum2-12B-A2.5B-Instruct](/compare/mellum2-12b-a2-5b-instruct-vs-mellum2-12b-a2-5b-thinking)
- [Qwen3.8-Omni-Flash vs Mellum2-12B-A2.5B-Instruct](/compare/mellum2-12b-a2-5b-instruct-vs-qwen3-8-omni-flash)
- [Mellum2-12B-A2.5B-Thinking vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-mellum2-12b-a2-5b-thinking)
- [Qwen3.8-Omni-Flash vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-qwen3-8-omni-flash)

## Explore More

- [Mellum2-12B-A2.5B-Thinking profile](/models/mellum2-12b-a2-5b-thinking)
- [Qwen3.8-Omni-Flash profile](/models/qwen3-8-omni-flash)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)