# LFM2.5-8B-A1B vs Mellum2-12B-A2.5B-Thinking

> Side-by-side benchmark comparison for LFM2.5-8B-A1B and Mellum2-12B-A2.5B-Thinking across agentic, coding, multimodal, knowledge, reasoning, multilingual, and math tasks.

- Canonical page: https://benchlm.ai/compare/lfm2-5-8b-a1b-vs-mellum2-12b-a2-5b-thinking
- 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: LFM2.5-8B-A1B and Mellum2-12B-A2.5B-Thinking 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.

## Model Snapshot

| Property | LFM2.5-8B-A1B | Mellum2-12B-A2.5B-Thinking |
|----------|----------|----------|
| Creator | LiquidAI | JetBrains |
| Type | Open Weight | Open Weight |
| Reasoning | Reasoning | Reasoning |
| Context | 128K | 128K |
| Independent public score (not head-to-head) | 41.42 | null |
| Benchmarks Covered | 7 | 6 |
| Pricing (input/output) | $0.00 / $0.00 | N/A |

## Category Breakdown

### Agentic

- Winner: Insufficient shared evidence
- LFM2.5-8B-A1B public-lane score: 45.5 (Estimated · #93/151)
- Mellum2-12B-A2.5B-Thinking public-lane score: 48.3 (Estimated · #76/151)

| Benchmark | LFM2.5-8B-A1B | Mellum2-12B-A2.5B-Thinking | Winner |
|-----------|-----------|-----------|--------|
| BFCL v4 | 49.7% | 45.6% | LFM2.5-8B-A1B |
| τ²-bench results | 88.1% | Coming soon | Coming soon |

### Coding

- Winner: Insufficient shared evidence
- LFM2.5-8B-A1B public-lane score: 45 (Estimated · #112/183)
- Mellum2-12B-A2.5B-Thinking public-lane score: Coming soon

| Benchmark | LFM2.5-8B-A1B | Mellum2-12B-A2.5B-Thinking | Winner |
|-----------|-----------|-----------|--------|
| LiveCodeBench v6 | Coming soon | 69.9% | Coming soon |

### Reasoning

- Winner: Insufficient shared evidence
- LFM2.5-8B-A1B public-lane score: 21 (Unranked · 2 rankable rows)
- Mellum2-12B-A2.5B-Thinking public-lane score: Coming soon

### Knowledge

- Winner: Insufficient shared evidence
- LFM2.5-8B-A1B public-lane score: 34.3 (Supported · #168/181)
- Mellum2-12B-A2.5B-Thinking public-lane score: 48.8 (Estimated · #96/181)

| Benchmark | LFM2.5-8B-A1B | Mellum2-12B-A2.5B-Thinking | Winner |
|-----------|-----------|-----------|--------|
| MMLU-Redux | Coming soon | 86.2% | Coming soon |
| GPQA | Coming soon | 57.6% | Coming soon |
| GPQA-D | Coming soon | 57.6% | Coming soon |

### Instruction Following

- Winner: Insufficient shared evidence
- LFM2.5-8B-A1B public-lane score: 44.7 (#92/120)
- Mellum2-12B-A2.5B-Thinking public-lane score: Coming soon

| Benchmark | LFM2.5-8B-A1B | Mellum2-12B-A2.5B-Thinking | Winner |
|-----------|-----------|-----------|--------|
| IFEval | 91.8% | 76.5% | LFM2.5-8B-A1B |
| IFBench | 56.5% | Coming soon | Coming soon |

### Mathematics

- Winner: Insufficient shared evidence
- LFM2.5-8B-A1B public-lane score: 27.7 (Unranked · 3 rankable rows)
- Mellum2-12B-A2.5B-Thinking public-lane score: Coming soon

| Benchmark | LFM2.5-8B-A1B | Mellum2-12B-A2.5B-Thinking | Winner |
|-----------|-----------|-----------|--------|
| MATH-500 | 88.8% | Coming soon | Coming soon |
| AIME 2025 | 42.5% | Coming soon | Coming soon |
| AIME26 | 50.0% | Coming soon | Coming soon |

## FAQ

### Is there enough evidence to pick between LFM2.5-8B-A1B and Mellum2-12B-A2.5B-Thinking?

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

- [LFM2.5-8B-A1B vs Mellum2-12B-A2.5B-Instruct](/compare/lfm2-5-8b-a1b-vs-mellum2-12b-a2-5b-instruct)
- [Mellum2-12B-A2.5B-Thinking vs Mellum2-12B-A2.5B-Instruct](/compare/mellum2-12b-a2-5b-instruct-vs-mellum2-12b-a2-5b-thinking)
- [LFM2.5-8B-A1B vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-lfm2-5-8b-a1b)
- [Mellum2-12B-A2.5B-Thinking vs Claude Fable 5.1](/compare/claude-fable-5-1-vs-mellum2-12b-a2-5b-thinking)

## Explore More

- [LFM2.5-8B-A1B profile](/models/lfm2-5-8b-a1b)
- [Mellum2-12B-A2.5B-Thinking profile](/models/mellum2-12b-a2-5b-thinking)
- [Compare Pricing](/llm-pricing)
- [Alternative Finder](/tools/alternative-finder)
- [LLM Selector](/tools/llm-selector)
- [Overall Rankings](/best/overall)