Model comparison
Claude Mythos 5 vs Gemma 4 31B
Head-to-head evidence from 3 shared benchmark results across 1 category. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Mythos 5 #1 (Supported); Gemma 4 31B #43 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Mythos 5 and Gemma 4 31B share 3 comparable benchmark results. 3 of 8 categories are comparable. 12 results are unique to Claude Mythos 5; 26 to Gemma 4 31B.
Updated July 23, 2026- Shared results
- 3
- Claude Mythos 5 only
- 12
- Gemma 4 31B only
- 26
- Comparable categories
- 3 / 8
Pick Claude Mythos 5 if you want the stronger benchmark profile. Gemma 4 31B only becomes the better choice if you want the cheaper token bill.
Confidence note. This is a partial-evidence comparison with 3 shared benchmark results across 1 evidence category; 3 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
Claude Mythos 5 is clearly ahead on the BenchAlign aggregate, 83.93 to 61.08. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
Claude Mythos 5's sharpest advantage is in coding, where it averages 89.7 against 41.6. The single biggest benchmark swing on the page is HLE, 64.5% to 26.5%.
Claude Mythos 5 is also the more expensive model on tokens at $10.00 input / $50.00 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. Claude Mythos 5 gives you the larger context window at 1M+, compared with 256K for Gemma 4 31B.
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 | Claude Mythos 5 | Δ | Gemma 4 31B |
|---|---|---|---|
| Coding | Claude Mythos 589.7 | Margin← 48.1 | Gemma 4 31B41.6 |
| Multimodal | Claude Mythos 593.5 | Margin← 16.6 | Gemma 4 31B76.9 |
| Knowledge | Claude Mythos 568.5 | Margin← 15.6 | Gemma 4 31B52.9 |
| Agentic | Claude Mythos 587.0 | MarginNo overlap | Gemma 4 31BNot measured |
| Math | Claude Mythos 597.6 | MarginNo overlap | Gemma 4 31BNot measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
HLE
KnowledgeA 64.5%B 26.5%Winner: Claude Mythos 5Δ 38HLE: Claude Mythos 5 scored 64.5%; Gemma 4 31B scored 26.5%. Claude Mythos 5 wins this benchmark. - Source ↗
GPQA
KnowledgeA 94.1%B 84.3%Winner: Claude Mythos 5Δ 9.8GPQA: Claude Mythos 5 scored 94.1%; Gemma 4 31B scored 84.3%. Claude Mythos 5 wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | Claude Mythos 5 | Gemma 4 31B | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Mythos 5$10 input / $50 output | Gemma 4 31B$0 input / $0 output | Gemma 4 31B has the lower combined listed price. |
| Generation speedtokens per second | Claude Mythos 5Not available | Gemma 4 31BNot available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Mythos 5Not available | Gemma 4 31BNot available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Mythos 51M+ | Gemma 4 31B256K | Claude Mythos 5 lists the larger context window. |
Benchmark Deep Dive
Agentic13 benchmarks
| Benchmark | Claude Mythos 5 | Gemma 4 31B | Result |
|---|---|---|---|
| Terminal-Bench 2.0Source | 88% | — | Not comparable |
| OSWorld-VerifiedSource | 85% | — | Not comparable |
| BrowseCompSource | 88% | — | Not comparable |
| ExploitGymSource | 17.5% | — | Not comparable |
| AA Agentic IndexSource | — | 14.4% | Not comparable |
| τ²-bench resultsSource | — | 59.9% | Not comparable |
| GDPval-AASource | — | 15.2% | Not comparable |
| GDPval-AASource | — | 804 | Not comparable |
| Gert LabsSource | — | 35.26% | Not comparable |
| AA EnterpriseOps-GymSource | — | 28.3% | Not comparable |
| AA ITBenchSource | — | 37.3% | Not comparable |
| AA Tau3 BankingSource | — | 15.1% | Not comparable |
| terminalBenchHardSource | — | 36.4% | Not comparable |
CodingClaude Mythos 5 wins7 benchmarks
| Benchmark | Claude Mythos 5 | Gemma 4 31B | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 95.5% | — | Not comparable |
| SWE-bench ProSource | 80.3% | — | Not comparable |
| Terminal-Bench 2.0Source | 88.0% | — | Not comparable |
| SWE-RebenchSource | — | 41.6% | Not comparable |
| React Native EvalsSource | — | 75.2% | Not comparable |
| AA Coding IndexSource | — | 43.4% | Not comparable |
| AA-SciCodeSource | — | 43.4% | Not comparable |
Reasoning2 benchmarks
KnowledgeClaude Mythos 5 wins11 benchmarks
| Benchmark | Claude Mythos 5 | Gemma 4 31B | Result |
|---|---|---|---|
| GPQASource | 94.1% | 84.3% | Claude Mythos 5 leads |
| HLESource | 64.5% | 26.5% | Claude Mythos 5 leads |
| HLE w/o toolsSource | 59% | 19.5% | Claude Mythos 5 leads |
| MMLU-ProSource | — | 85.2% | Not comparable |
| Artificial Analysis Intelligence IndexSource | — | 29.4% | Not comparable |
| AA-GPQA DiamondSource | — | 85.7% | Not comparable |
| AA-HLESource | — | 22.7% | Not comparable |
| AA-Omniscience IndexSource | — | -45.4% | Not comparable |
| AA-Omniscience AccuracySource | — | 19.9% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 81.6% | Not comparable |
| AA Openness IndexSource | — | 38.9% | Not comparable |
Math1 benchmarks
| Benchmark | Claude Mythos 5 | Gemma 4 31B | Result |
|---|---|---|---|
| USAMO 2026Source | 97.6% | — | Not comparable |
Multilingual1 benchmarks
| Benchmark | Claude Mythos 5 | Gemma 4 31B | Result |
|---|---|---|---|
| SWE MultilingualSource | 92.2% | — | Not comparable |
MultimodalClaude Mythos 5 wins5 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Mythos 5 | Gemma 4 31B | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 75.6% | Not comparable |
Frequently Asked Questions (4)
Which is better, Claude Mythos 5 or Gemma 4 31B?
Claude Mythos 5 is ahead on BenchLM's BenchAlign leaderboard, 83.93 to 61.08. The biggest single separator in this matchup is HLE, where the scores are 64.5% and 26.5%.
Which is better for knowledge tasks, Claude Mythos 5 or Gemma 4 31B?
Claude Mythos 5 has the edge for knowledge tasks in this comparison, averaging 68.5 versus 52.9. Inside this category, HLE w/o tools is the benchmark that creates the most daylight between them.
Which is better for coding, Claude Mythos 5 or Gemma 4 31B?
Claude Mythos 5 has the edge for coding in this comparison, averaging 89.7 versus 41.6. Gemma 4 31B stays close enough that the answer can still flip depending on your workload.
Which is better for multimodal and grounded tasks, Claude Mythos 5 or Gemma 4 31B?
Claude Mythos 5 has the edge for multimodal and grounded tasks in this comparison, averaging 93.5 versus 76.9. Gemma 4 31B stays close enough that the answer can still flip depending on your workload.
Self-host vs API cost
Estimates at 50,000 req/day · 1000 tokens/req average.
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