Model comparison
Claude Mythos 5 vs Gemini 2.5 Pro
Head-to-head evidence from 3 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: Claude Mythos 5 #1 (Supported); Gemini 2.5 Pro #70 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude Mythos 5 and Gemini 2.5 Pro share 3 comparable benchmark results. 3 of 8 categories are comparable. 12 results are unique to Claude Mythos 5; 21 to Gemini 2.5 Pro.
Updated July 23, 2026- Shared results
- 3
- Claude Mythos 5 only
- 12
- Gemini 2.5 Pro only
- 21
- Comparable categories
- 3 / 8
Pick Claude Mythos 5 if you want the stronger benchmark profile. Gemini 2.5 Pro 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 3 shared benchmark results across 2 evidence categories; 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 57.25. 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 mathematics, where it averages 97.6 against 11.6. The single biggest benchmark swing on the page is HLE, 64.5% to 18.8%.
Claude Mythos 5 is also the more expensive model on tokens at $10.00 input / $50.00 output per 1M tokens, versus $1.25 input / $10.00 output per 1M tokens for Gemini 2.5 Pro. That is roughly 5.0x on output cost alone. Claude Mythos 5 is the reasoning model in the pair, while Gemini 2.5 Pro 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 2.5 Pro.
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 2.5 Pro |
|---|---|---|---|
| Math | Claude Mythos 597.6 | Margin← 86.0 | Gemini 2.5 Pro11.6 |
| Knowledge | Claude Mythos 568.5 | Margin← 41.1 | Gemini 2.5 Pro27.4 |
| Coding | Claude Mythos 589.7 | Margin← 25.9 | Gemini 2.5 Pro63.8 |
| Agentic | Claude Mythos 587.0 | MarginNo overlap | Gemini 2.5 ProNot measured |
| Multimodal | Claude Mythos 593.5 | MarginNo overlap | Gemini 2.5 ProNot measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
HLE
KnowledgeA 64.5%B 18.8%Winner: Claude Mythos 5Δ 45.7HLE: Claude Mythos 5 scored 64.5%; Gemini 2.5 Pro scored 18.8%. Claude Mythos 5 wins this benchmark. - Source ↗
SWE-bench Verified
CodingA 95.5%B 63.8%Winner: Claude Mythos 5Δ 31.7SWE-bench Verified: Claude Mythos 5 scored 95.5%; Gemini 2.5 Pro scored 63.8%. Claude Mythos 5 wins this benchmark. - Source ↗
GPQA
KnowledgeA 94.1%B 83%Winner: Claude Mythos 5Δ 11.1GPQA: Claude Mythos 5 scored 94.1%; Gemini 2.5 Pro scored 83%. 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 2.5 Pro | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude Mythos 5$10 input / $50 output | Gemini 2.5 Pro$1.25 input / $10 output | Gemini 2.5 Pro has the lower combined listed price. |
| Generation speedtokens per second | Claude Mythos 5Not available | Gemini 2.5 Pro117 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude Mythos 5Not available | Gemini 2.5 Pro21.19 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude Mythos 51M+ | Gemini 2.5 Pro1M | Claude Mythos 5 lists the larger context window. |
Benchmark Deep Dive
Agentic9 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 2.5 Pro | 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 | — | 7.1% | Not comparable |
| τ²-bench resultsSource | — | 54.1% | Not comparable |
| Gert LabsSource | — | 42.01% | Not comparable |
| GDPval-AASource | — | 8.3% | Not comparable |
| GDPval-AASource | — | 665 | Not comparable |
CodingClaude Mythos 5 wins6 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 2.5 Pro | Result |
|---|---|---|---|
| SWE-bench VerifiedSource | 95.5% | 63.8% | Claude Mythos 5 leads |
| SWE-bench ProSource | 80.3% | — | Not comparable |
| Terminal-Bench 2.0Source | 88.0% | — | Not comparable |
| Vibe Code BenchSource | — | 0.40% | Not comparable |
| AA Coding IndexSource | — | 33.3% | Not comparable |
| AA-SciCodeSource | — | 42.8% | Not comparable |
Reasoning2 benchmarks
KnowledgeClaude Mythos 5 wins9 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 2.5 Pro | Result |
|---|---|---|---|
| GPQASource | 94.1% | 83% | Claude Mythos 5 leads |
| HLESource | 64.5% | 18.8% | Claude Mythos 5 leads |
| HLE w/o toolsSource | 59% | — | 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 |
MathClaude Mythos 5 wins3 benchmarks
Multilingual1 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 2.5 Pro | Result |
|---|---|---|---|
| SWE MultilingualSource | 92.2% | — | Not comparable |
Multimodal5 benchmarks
Inst. Following1 benchmarks
| Benchmark | Claude Mythos 5 | Gemini 2.5 Pro | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 48.7% | Not comparable |
Frequently Asked Questions (4)
Which is better, Claude Mythos 5 or Gemini 2.5 Pro?
Claude Mythos 5 is ahead on BenchLM's BenchAlign leaderboard, 83.93 to 57.25. The biggest single separator in this matchup is HLE, where the scores are 64.5% and 18.8%.
Which is better for knowledge tasks, Claude Mythos 5 or Gemini 2.5 Pro?
Claude Mythos 5 has the edge for knowledge tasks in this comparison, averaging 68.5 versus 27.4. Inside this category, HLE is the benchmark that creates the most daylight between them.
Which is better for coding, Claude Mythos 5 or Gemini 2.5 Pro?
Claude Mythos 5 has the edge for coding in this comparison, averaging 89.7 versus 63.8. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.
Which is better for math, Claude Mythos 5 or Gemini 2.5 Pro?
Claude Mythos 5 has the edge for math in this comparison, averaging 97.6 versus 11.6. Gemini 2.5 Pro stays close enough that the answer can still flip depending on your workload.
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