Model comparison
Gemma 4 12B vs GPT-5.5 Pro
Head-to-head evidence from 2 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Gemma 4 12B #137 (Estimated); GPT-5.5 Pro #38 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Gemma 4 12B and GPT-5.5 Pro share 2 comparable benchmark results. 2 of 8 categories are comparable. 21 results are unique to Gemma 4 12B; 5 to GPT-5.5 Pro.
Updated July 23, 2026- Shared results
- 2
- Gemma 4 12B only
- 21
- GPT-5.5 Pro only
- 5
- Comparable categories
- 2 / 8
Pick GPT-5.5 Pro if you want the stronger benchmark profile. Gemma 4 12B only becomes the better choice if mathematics is the priority.
Confidence note. This is a partial-evidence comparison with 2 shared benchmark results across 2 evidence categories; 2 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
GPT-5.5 Pro is clearly ahead on the BenchAlign aggregate, 63.69 to 47.29. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
GPT-5.5 Pro gives you the larger context window at 1M, compared with 256K for Gemma 4 12B.
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 | Gemma 4 12B | Δ | GPT-5.5 Pro |
|---|---|---|---|
| Math | Gemma 4 12B77.5 | Margin← 29.4 | GPT-5.5 Pro48.1 |
| Knowledge | Gemma 4 12B77.5 | Margin← 20.3 | GPT-5.5 Pro57.2 |
| Agentic | Gemma 4 12BNot measured | MarginNo overlap | GPT-5.5 Pro90.1 |
| Reasoning | Gemma 4 12B43.4 | MarginNo overlap | GPT-5.5 ProNot measured |
| Multimodal | Gemma 4 12B69.1 | MarginNo overlap | GPT-5.5 ProNot measured |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Gemma 4 12B | GPT-5.5 Pro | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Gemma 4 12BNot available | GPT-5.5 Pro$30 input / $180 output | A complete price comparison is not available. |
| Generation speedtokens per second | Gemma 4 12BNot available | GPT-5.5 ProNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Gemma 4 12BNot available | GPT-5.5 ProNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Gemma 4 12B256K | GPT-5.5 Pro1M | GPT-5.5 Pro lists the larger context window. |
Benchmark Deep Dive
Agentic2 benchmarks
Coding1 benchmarks
| Benchmark | Gemma 4 12B | GPT-5.5 Pro | Result |
|---|---|---|---|
| AA-SciCodeSource | 38.2% | — | Not comparable |
Reasoning4 benchmarks
KnowledgeGemma 4 12B wins12 benchmarks
| Benchmark | Gemma 4 12B | GPT-5.5 Pro | Result |
|---|---|---|---|
| GPQASource | 78.8% | — | Not comparable |
| GPQA-DSource | 78.8% | — | Not comparable |
| MMLU-ProSource | 77.2% | — | Not comparable |
| HLE w/o toolsSource | 5.2% | 43.1% | GPT-5.5 Pro leads |
| MMMLUSource | 83.4% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 22.0% | — | Not comparable |
| AA-GPQA DiamondSource | 75.3% | — | Not comparable |
| AA-HLESource | 14.8% | — | Not comparable |
| AA-Omniscience IndexSource | -51.9% | — | Not comparable |
| AA-Omniscience AccuracySource | 16.0% | — | Not comparable |
| AA-Omniscience Hallucination RateSource | 80.8% | — | Not comparable |
| HLESource | — | 57.2% | Not comparable |
MathGemma 4 12B wins4 benchmarks
Multimodal4 benchmarks
Inst. Following1 benchmarks
| Benchmark | Gemma 4 12B | GPT-5.5 Pro | Result |
|---|---|---|---|
| AA-IFBenchSource | 73.5% | — | Not comparable |
Frequently Asked Questions (3)
Which is better, Gemma 4 12B or GPT-5.5 Pro?
GPT-5.5 Pro is ahead on BenchLM's BenchAlign leaderboard, 63.69 to 47.29.
Which is better for knowledge tasks, Gemma 4 12B or GPT-5.5 Pro?
Gemma 4 12B has the edge for knowledge tasks in this comparison, averaging 77.5 versus 57.2. Inside this category, HLE w/o tools is the benchmark that creates the most daylight between them.
Which is better for math, Gemma 4 12B or GPT-5.5 Pro?
Gemma 4 12B has the edge for math in this comparison, averaging 77.5 versus 48.1. GPT-5.5 Pro stays close enough that the answer can still flip depending on your workload.
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