Model comparison
Claude Mythos 5 vs Gemini 3.1 Flash-Lite
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: Claude Mythos 5 #1 (Supported); Gemini 3.1 Flash-Lite #111 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Mythos 5 and Gemini 3.1 Flash-Lite share 1 comparable benchmark result. 1 of 8 categories are comparable. 14 results are unique to Claude Mythos 5; 19 to Gemini 3.1 Flash-Lite.
Updated July 23, 2026- Shared results
- 1
- Claude Mythos 5 only
- 14
- Gemini 3.1 Flash-Lite only
- 19
- Comparable categories
- 1 / 8
Pick Claude Mythos 5 if you want the stronger benchmark profile. Gemini 3.1 Flash-Lite only becomes the better choice if you want the cheaper token bill or you would rather avoid the extra latency and token burn of a reasoning model.
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
Claude Mythos 5 is clearly ahead on the BenchAlign aggregate, 83.93 to 50.83. 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 multimodal & grounded, where it averages 93.5 against 73.2. The single biggest benchmark swing on the page is CharXiv, 93.5% to 73.2%.
Claude Mythos 5 is also the more expensive model on tokens at $10.00 input / $50.00 output per 1M tokens, versus $0.25 input / $1.50 output per 1M tokens for Gemini 3.1 Flash-Lite. That is roughly 33.3x on output cost alone. Claude Mythos 5 is the reasoning model in the pair, while Gemini 3.1 Flash-Lite is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. Claude Mythos 5 gives you the larger context window at 1M+, compared with 1M for Gemini 3.1 Flash-Lite.
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 | Gemini 3.1 Flash-Lite |
|---|---|---|---|
| Multimodal | Claude Mythos 593.5 | Margin← 20.3 | Gemini 3.1 Flash-Lite73.2 |
| Agentic | Claude Mythos 587.0 | MarginNo overlap | Gemini 3.1 Flash-LiteNot measured |
| Coding | Claude Mythos 589.7 | MarginNo overlap | Gemini 3.1 Flash-LiteNot measured |
| Knowledge | Claude Mythos 568.5 | MarginNo overlap | Gemini 3.1 Flash-LiteNot measured |
| Math | Claude Mythos 597.6 | MarginNo overlap | Gemini 3.1 Flash-LiteNot measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
CharXiv
MultimodalA 93.5%B 73.2%Winner: Claude Mythos 5Δ 20.3CharXiv: Claude Mythos 5 scored 93.5%; Gemini 3.1 Flash-Lite scored 73.2%. 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 | Gemini 3.1 Flash-Lite | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Mythos 5$10 input / $50 output | Gemini 3.1 Flash-Lite$0.25 input / $1.5 output | Gemini 3.1 Flash-Lite has the lower combined listed price. |
| Generation speedtokens per second | Claude Mythos 5Not available | Gemini 3.1 Flash-Lite205 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Mythos 5Not available | Gemini 3.1 Flash-Lite7.50 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Mythos 51M+ | Gemini 3.1 Flash-Lite1M | Claude Mythos 5 lists the larger context window. |
Benchmark Deep Dive
Agentic10 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 3.1 Flash-Lite | 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 | — | 6.2% | Not comparable |
| APEX-Agents-AASource | — | 12.2% | Not comparable |
| τ²-bench resultsSource | — | 31.3% | Not comparable |
| GDPval-AASource | — | 7.1% | Not comparable |
| GDPval-AASource | — | 642 | Not comparable |
| Gert LabsSource | — | 38.46% | Not comparable |
Coding6 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 3.1 Flash-Lite | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 95.5% | — | Not comparable |
| SWE-bench ProSource | 80.3% | — | Not comparable |
| Terminal-Bench 2.0Source | 88.0% | — | Not comparable |
| Vibe Code BenchSource | — | 0.00% | Not comparable |
| AA Coding IndexSource | — | 34.7% | Not comparable |
| AA-SciCodeSource | — | 41.9% | Not comparable |
Reasoning2 benchmarks
Knowledge9 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 3.1 Flash-Lite | Result |
|---|---|---|---|
| GPQASource | 94.1% | — | Not comparable |
| HLESource | 64.5% | — | Not comparable |
| HLE w/o toolsSource | 59% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | — | 25.0% | Not comparable |
| AA-GPQA DiamondSource | — | 82.2% | Not comparable |
| AA-HLESource | — | 16.2% | Not comparable |
| AA-Omniscience IndexSource | — | -15.5% | Not comparable |
| AA-Omniscience AccuracySource | — | 36.4% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 81.6% | Not comparable |
Math1 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 3.1 Flash-Lite | Result |
|---|---|---|---|
| USAMO 2026Source | 97.6% | — | Not comparable |
Multilingual1 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 3.1 Flash-Lite | Result |
|---|---|---|---|
| SWE MultilingualSource | 92.2% | — | Not comparable |
MultimodalClaude Mythos 5 wins4 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 3.1 Flash-Lite | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 77.2% | Not comparable |
Frequently Asked Questions (2)
Which is better, Claude Mythos 5 or Gemini 3.1 Flash-Lite?
Claude Mythos 5 is ahead on BenchLM's BenchAlign leaderboard, 83.93 to 50.83. The biggest single separator in this matchup is CharXiv, where the scores are 93.5% and 73.2%.
Which is better for multimodal and grounded tasks, Claude Mythos 5 or Gemini 3.1 Flash-Lite?
Claude Mythos 5 has the edge for multimodal and grounded tasks in this comparison, averaging 93.5 versus 73.2. Inside this category, CharXiv is the benchmark that creates the most daylight between them.
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