# Claude Opus 4.7 (Adaptive) vs Mellum2-12B-A2.5B-Instruct

> Side-by-side benchmark comparison for Claude Opus 4.7 (Adaptive) and Mellum2-12B-A2.5B-Instruct across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/claude-opus-4-7-adaptive-vs-mellum2-12b-a2-5b-instruct
- Last updated: September 4, 2026

- Shared sourced benchmarks: 2
- HTML indexing: indexable
- Ranking lane: BenchAlign v5

## Quick Verdict

Evidence is too thin for a benchmark verdict: Claude Opus 4.7 (Adaptive) and Mellum2-12B-A2.5B-Instruct share only 2 sourced benchmark rows.

## Summary

- Only 2 shared sourced benchmark rows are available. That is not enough for a broad capability verdict, so this mirror does not name an overall winner.
- Claude Opus 4.7 (Adaptive) has the larger published context window at 1M.

## Model Snapshot

| Property | Claude Opus 4.7 (Adaptive) | Mellum2-12B-A2.5B-Instruct |
|----------|----------|----------|
| Creator | Anthropic | JetBrains |
| Type | Proprietary | Open Weight |
| Reasoning | Reasoning | Non-Reasoning |
| Context | 1M | 128K |
| Independent public score (not head-to-head) | 69.94 | null |
| Benchmarks Covered | 21 | 6 |
| Pricing (input/output) | $5.00 / $25.00 | N/A |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- Claude Opus 4.7 (Adaptive) public-lane score: 61 (Supported · #21/151)
- Mellum2-12B-A2.5B-Instruct public-lane score: 47.8 (Estimated · #82/151)

| Benchmark | Claude Opus 4.7 (Adaptive) | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| Terminal-Bench 2.0 | 69.4% | Coming soon | Coming soon |
| BrowseComp | 79.3% | Coming soon | Coming soon |
| MCP Atlas | 77.3% | Coming soon | Coming soon |
| OSWorld-Verified | 78% | Coming soon | Coming soon |
| CyberGym | 73.1% | Coming soon | Coming soon |
| OSWorld 2.0 | 18.2% | Coming soon | Coming soon |
| JobBench | 45.9% | Coming soon | Coming soon |
| BFCL v4 | Coming soon | 44.2% | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- Claude Opus 4.7 (Adaptive) public-lane score: 59.6 (Estimated · #27/183)
- Mellum2-12B-A2.5B-Instruct public-lane score: Coming soon

| Benchmark | Claude Opus 4.7 (Adaptive) | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| SWE-bench Verified | 87.6% | Coming soon | Coming soon |
| SWE-bench Pro | 64.3% | Coming soon | Coming soon |
| Terminal-Bench 2.0 | 69.4% | Coming soon | Coming soon |
| LiveCodeBench v6 | Coming soon | 37.2% | Coming soon |

### Multimodal & Grounded

- Winner: Insufficient shared evidence
- Claude Opus 4.7 (Adaptive) public-lane score: 50.3 (#36/48)
- Mellum2-12B-A2.5B-Instruct public-lane score: Coming soon

| Benchmark | Claude Opus 4.7 (Adaptive) | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| OfficeQA Pro | 43.6% | Coming soon | Coming soon |
| CharXiv | 91% | Coming soon | Coming soon |
| CharXiv w/o tools | 82.1% | Coming soon | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- Claude Opus 4.7 (Adaptive) public-lane score: 49.7 (Unranked · 3 rankable rows)
- Mellum2-12B-A2.5B-Instruct public-lane score: Coming soon

| Benchmark | Claude Opus 4.7 (Adaptive) | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| MRCR v2 128K-256K | 59.2% | Coming soon | Coming soon |
| ARC-AGI-2 | 75.8% | Coming soon | Coming soon |
| ARC-AGI-3 | 0.2% | Coming soon | Coming soon |

### Knowledge

- Winner: Insufficient shared evidence
- Claude Opus 4.7 (Adaptive) public-lane score: 61.9 (Estimated · #31/181)
- Mellum2-12B-A2.5B-Instruct public-lane score: 48.1 (Estimated · #103/181)

| Benchmark | Claude Opus 4.7 (Adaptive) | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| GPQA | 94.2% | 40.9% | Claude Opus 4.7 (Adaptive) |
| GPQA-D | 94.2% | 40.9% | Claude Opus 4.7 (Adaptive) |
| HLE | 54.7% | Coming soon | Coming soon |
| HLE w/o tools | 46.9% | Coming soon | Coming soon |
| MMLU-Redux | Coming soon | 78.1% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- Claude Opus 4.7 (Adaptive) public-lane score: Coming soon
- Mellum2-12B-A2.5B-Instruct public-lane score: Coming soon

| Benchmark | Claude Opus 4.7 (Adaptive) | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| IFEval | Coming soon | 75.8% | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- Claude Opus 4.7 (Adaptive) public-lane score: Coming soon
- Mellum2-12B-A2.5B-Instruct public-lane score: Coming soon

| Benchmark | Claude Opus 4.7 (Adaptive) | Mellum2-12B-A2.5B-Instruct | Winner |
|-----------|-----------|-----------|--------|
| FrontierMath (legacy) | 43.8% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between Claude Opus 4.7 (Adaptive) and Mellum2-12B-A2.5B-Instruct?

Not yet. The models share only 2 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

- [Claude Opus 4.7 (Adaptive) vs Claude Opus 4.7](/compare/claude-opus-4-7-vs-claude-opus-4-7-adaptive)
- [Mellum2-12B-A2.5B-Instruct vs Claude Opus 4.7](/compare/claude-opus-4-7-vs-mellum2-12b-a2-5b-instruct)
- [Claude Opus 4.7 (Adaptive) vs Mellum2-12B-A2.5B-Thinking](/compare/claude-opus-4-7-adaptive-vs-mellum2-12b-a2-5b-thinking)
- [Mellum2-12B-A2.5B-Instruct vs Mellum2-12B-A2.5B-Thinking](/compare/mellum2-12b-a2-5b-instruct-vs-mellum2-12b-a2-5b-thinking)

## Explore More

- [Claude Opus 4.7 (Adaptive) profile](/models/claude-opus-4-7-adaptive)
- [Mellum2-12B-A2.5B-Instruct profile](/models/mellum2-12b-a2-5b-instruct)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)