Model comparison
Gemini 2.5 Pro vs Mellum2-12B-A2.5B-Instruct
Head-to-head evidence from 1 shared benchmark result across 1 category. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Gemini 2.5 Pro #70 (Supported); Mellum2-12B-A2.5B-Instruct unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Gemini 2.5 Pro and Mellum2-12B-A2.5B-Instruct share 1 comparable benchmark result. 1 of 8 categories are comparable. 23 results are unique to Gemini 2.5 Pro; 4 to Mellum2-12B-A2.5B-Instruct.
Updated July 23, 2026- Shared results
- 1
- Gemini 2.5 Pro only
- 23
- Mellum2-12B-A2.5B-Instruct only
- 4
- Comparable categories
- 1 / 8
Treat this as a split decision. Gemini 2.5 Pro makes more sense if you need the larger 1M context window; Mellum2-12B-A2.5B-Instruct is the better fit if knowledge is the priority.
Confidence note. This is a partial-evidence comparison with 1 shared benchmark result across 1 evidence category; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Gemini 2.5 Pro and Mellum2-12B-A2.5B-Instruct finish on the same BenchAlign overall score, so this is less about a single winner and more about where the edge shows up. The BenchAlign headline says tie; the benchmark table is where the real choice happens.
Gemini 2.5 Pro gives you the larger context window at 1M, compared with 128K for Mellum2-12B-A2.5B-Instruct.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | Gemini 2.5 Pro | Δ | Mellum2-12B-A2.5B-Instruct |
|---|---|---|---|
| Knowledge | Gemini 2.5 Pro27.4 | Margin→ 13.5 | Mellum2-12B-A2.5B-Instruct40.9 |
| Coding | Gemini 2.5 Pro63.8 | MarginNo overlap | Mellum2-12B-A2.5B-InstructNot measured |
| Math | Gemini 2.5 Pro11.6 | MarginNo overlap | Mellum2-12B-A2.5B-InstructNot measured |
| Inst. Following | Gemini 2.5 ProNot measured | MarginNo overlap | Mellum2-12B-A2.5B-Instruct75.8 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
GPQA
KnowledgeA 83%B 40.9%Winner: Gemini 2.5 ProΔ 42.1GPQA: Gemini 2.5 Pro scored 83%; Mellum2-12B-A2.5B-Instruct scored 40.9%. Gemini 2.5 Pro wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Gemini 2.5 Pro | Mellum2-12B-A2.5B-Instruct | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Gemini 2.5 Pro$1.25 input / $10 output | Mellum2-12B-A2.5B-InstructNot available | A complete price comparison is not available. |
| Generation speedtokens per second | Gemini 2.5 Pro117 tok/s | Mellum2-12B-A2.5B-InstructNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Gemini 2.5 Pro21.19 s | Mellum2-12B-A2.5B-InstructNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Gemini 2.5 Pro1M | Mellum2-12B-A2.5B-Instruct128K | Gemini 2.5 Pro lists the larger context window. |
Benchmark Deep Dive
Agentic6 benchmarks
Coding4 benchmarks
Reasoning2 benchmarks
KnowledgeMellum2-12B-A2.5B-Instruct wins10 benchmarks
| Benchmark | Gemini 2.5 Pro | Mellum2-12B-A2.5B-Instruct | Result |
|---|---|---|---|
| GPQASource | 83% | 40.9% | Gemini 2.5 Pro leads |
| HLESource | 18.8% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 25.8% | — | Not comparable |
| AA-GPQA DiamondSource | 84.4% | — | Not comparable |
| AA-HLESource | 21.1% | — | Not comparable |
| AA-Omniscience IndexSource | -14.3% | — | Not comparable |
| AA-Omniscience AccuracySource | 39.0% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 87.4% | — | Not comparable |
| MMLU-ReduxSource | — | 78.1% | Not comparable |
| GPQA-DSource | — | 40.9% | Not comparable |
Math2 benchmarks
Multimodal2 benchmarks
Frequently Asked Questions (2)
Which is better, Gemini 2.5 Pro or Mellum2-12B-A2.5B-Instruct?
Gemini 2.5 Pro and Mellum2-12B-A2.5B-Instruct are tied on the BenchAlign overall score, so the right pick depends on which category matters most for your use case.
Which is better for knowledge tasks, Gemini 2.5 Pro or Mellum2-12B-A2.5B-Instruct?
Mellum2-12B-A2.5B-Instruct has the edge for knowledge tasks in this comparison, averaging 40.9 versus 27.4. Inside this category, GPQA is the benchmark that creates the most daylight between them.
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