Model comparison
Gemma 4 31B vs Mistral Medium 3.5 128B
Head-to-head evidence from 22 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Gemma 4 31B #47 (Supported); Mistral Medium 3.5 128B unranked (Not scored). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Gemma 4 31B and Mistral Medium 3.5 128B share 22 comparable benchmark results. 1 of 8 categories are comparable. 8 results are unique to Gemma 4 31B; 3 to Mistral Medium 3.5 128B.
Updated July 27, 2026- Shared results
- 22
- Gemma 4 31B only
- 8
- Mistral Medium 3.5 128B only
- 3
- Comparable categories
- 1 / 8
Treat this as a split decision. Gemma 4 31B makes more sense if you want the cheaper token bill; Mistral Medium 3.5 128B is the better fit if coding is the priority.
Confidence note. This is a partial-evidence comparison with 22 shared benchmark results across 6 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Gemma 4 31B and Mistral Medium 3.5 128B 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.
Mistral Medium 3.5 128B is also the more expensive model on tokens at $1.50 input / $7.50 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for Gemma 4 31B. That is roughly Infinityx on output cost alone.
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 31B | Δ | Mistral Medium 3.5 128B |
|---|---|---|---|
| Coding | Gemma 4 31B41.6 | Margin→ 36.0 | Mistral Medium 3.5 128B77.6 |
| Knowledge | Gemma 4 31B52.9 | MarginNo overlap | Mistral Medium 3.5 128BNot measured |
| Multimodal | Gemma 4 31B76.9 | MarginNo overlap | Mistral Medium 3.5 128BNot measured |
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Gemma 4 31B | Mistral Medium 3.5 128B | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Gemma 4 31B$0 input / $0 output | Mistral Medium 3.5 128B$1.5 input / $7.5 output | Gemma 4 31B has the lower combined listed price. |
| Generation speedtokens per second | Gemma 4 31BNot available | Mistral Medium 3.5 128BNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Gemma 4 31BNot available | Mistral Medium 3.5 128BNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Gemma 4 31B256K | Mistral Medium 3.5 128B256K | Listed context windows are equal. |
Benchmark Deep Dive
Agentic12 benchmarks
| Benchmark | Gemma 4 31B | Mistral Medium 3.5 128B | Result |
|---|---|---|---|
| AA Agentic IndexSource | 14.4% | 19.0% | Mistral Medium 3.5 128B leads |
| τ²-bench resultsSource | 59.9% | 94.2% | Mistral Medium 3.5 128B leads |
| GDPval-AASource | 15.5% | 21.6% | Mistral Medium 3.5 128B leads |
| GDPval-AASource | 811 | 933 | Mistral Medium 3.5 128B leads |
| Gert LabsSource | 35.26% | 39.10% | Mistral Medium 3.5 128B leads |
| AA EnterpriseOps-GymSource | 28.3% | 33.7% | Mistral Medium 3.5 128B leads |
| AA ITBenchSource | 37.3% | — | Not comparable |
| terminalBenchHardSource | 36.4% | 33.3% | Gemma 4 31B leads |
| AA Harvey LABSource | 47.2% | 69.1% | Mistral Medium 3.5 128B leads |
| AA Tau3 BankingSource | 15.1% | 14.4% | Gemma 4 31B leads |
| τ³-bench resultsSource | — | 91.4% | Not comparable |
| AA BriefcaseSource | — | 516 | Not comparable |
CodingMistral Medium 3.5 128B wins5 benchmarks
Reasoning2 benchmarks
Knowledge11 benchmarks
| Benchmark | Gemma 4 31B | Mistral Medium 3.5 128B | Result |
|---|---|---|---|
| GPQASource | 84.3% | — | Not comparable |
| MMLU-ProSource | 85.2% | — | Not comparable |
| HLESource | 26.5% | — | Not comparable |
| HLE w/o toolsSource | 19.5% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | 29.4% | 29.9% | Mistral Medium 3.5 128B leads |
| AA-GPQA DiamondSource | 85.7% | 74.8% | Gemma 4 31B leads |
| AA-HLESource | 22.7% | 12.8% | Gemma 4 31B leads |
| AA-Omniscience IndexSource | -45.4% | -36.3% | Mistral Medium 3.5 128B leads |
| AA-Omniscience AccuracySource | 19.9% | 25.1% | Mistral Medium 3.5 128B leads |
| AA-Omniscience Hallucination RateSource | 81.6% | 82.0% | Gemma 4 31B leads |
| AA Openness IndexSource | 38.9% | 33.3% | Gemma 4 31B leads |
Multimodal2 benchmarks
Inst. Following1 benchmarks
| Benchmark | Gemma 4 31B | Mistral Medium 3.5 128B | Result |
|---|---|---|---|
| AA-IFBenchSource | 75.6% | 68.8% | Gemma 4 31B leads |
Frequently Asked Questions (2)
Which is better, Gemma 4 31B or Mistral Medium 3.5 128B?
Gemma 4 31B and Mistral Medium 3.5 128B 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 coding, Gemma 4 31B or Mistral Medium 3.5 128B?
Mistral Medium 3.5 128B has the edge for coding in this comparison, averaging 77.6 versus 41.6. Inside this category, AA-SciCode is the benchmark that creates the most daylight between them.
Self-host vs API cost
Estimates at 50,000 req/day · 1000 tokens/req average.
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