Model comparison
Claude 3.5 Sonnet vs Claude Mythos 5
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: Claude 3.5 Sonnet #132 (Estimated); Claude Mythos 5 #1 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. Claude 3.5 Sonnet and Claude Mythos 5 share 2 comparable benchmark results. 3 of 8 categories are comparable. 2 results are unique to Claude 3.5 Sonnet; 13 to Claude Mythos 5.
Updated July 23, 2026- Shared results
- 2
- Claude 3.5 Sonnet only
- 2
- Claude Mythos 5 only
- 13
- Comparable categories
- 3 / 8
Pick Claude Mythos 5 if you want the stronger benchmark profile. Claude 3.5 Sonnet 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 2 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 47.74. 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 1.6. The single biggest benchmark swing on the page is SWE-bench Verified, 49% to 95.5%.
Claude Mythos 5 is also the more expensive model on tokens at $10.00 input / $50.00 output per 1M tokens, versus $3.00 input / $15.00 output per 1M tokens for Claude 3.5 Sonnet. That is roughly 3.3x on output cost alone. Claude Mythos 5 is the reasoning model in the pair, while Claude 3.5 Sonnet 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 200K for Claude 3.5 Sonnet.
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 3.5 Sonnet | Δ | Claude Mythos 5 |
|---|---|---|---|
| Math | Claude 3.5 Sonnet1.6 | Margin→ 96.0 | Claude Mythos 597.6 |
| Coding | Claude 3.5 Sonnet49.0 | Margin→ 40.7 | Claude Mythos 589.7 |
| Knowledge | Claude 3.5 Sonnet59.4 | Margin→ 9.1 | Claude Mythos 568.5 |
| Agentic | Claude 3.5 SonnetNot measured | MarginNo overlap | Claude Mythos 587.0 |
| Multimodal | Claude 3.5 SonnetNot measured | MarginNo overlap | Claude Mythos 593.5 |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
SWE-bench Verified
CodingA 49%B 95.5%Winner: Claude Mythos 5Δ 46.5SWE-bench Verified: Claude 3.5 Sonnet scored 49%; Claude Mythos 5 scored 95.5%. Claude Mythos 5 wins this benchmark. - Source ↗
GPQA
KnowledgeA 59.4%B 94.1%Winner: Claude Mythos 5Δ 34.7GPQA: Claude 3.5 Sonnet scored 59.4%; Claude Mythos 5 scored 94.1%. 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 3.5 Sonnet | Claude Mythos 5 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | Claude 3.5 Sonnet$3 input / $15 output | Claude Mythos 5$10 input / $50 output | Claude 3.5 Sonnet has the lower combined listed price. |
| Generation speedtokens per second | Claude 3.5 SonnetNot available | Claude Mythos 5Not available | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | Claude 3.5 SonnetNot available | Claude Mythos 5Not available | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | Claude 3.5 Sonnet200K | Claude Mythos 51M+ | Claude Mythos 5 lists the larger context window. |
Benchmark Deep Dive
Agentic4 benchmarks
CodingClaude Mythos 5 wins3 benchmarks
KnowledgeClaude Mythos 5 wins3 benchmarks
MathClaude Mythos 5 wins3 benchmarks
Multilingual1 benchmarks
| Benchmark | Claude 3.5 Sonnet | Claude Mythos 5 | Result |
|---|---|---|---|
| SWE MultilingualSource | — | 92.2% | Not comparable |
Frequently Asked Questions (4)
Which is better, Claude 3.5 Sonnet or Claude Mythos 5?
Claude Mythos 5 is ahead on BenchLM's BenchAlign leaderboard, 83.93 to 47.74. The biggest single separator in this matchup is SWE-bench Verified, where the scores are 49% and 95.5%.
Which is better for knowledge tasks, Claude 3.5 Sonnet or Claude Mythos 5?
Claude Mythos 5 has the edge for knowledge tasks in this comparison, averaging 68.5 versus 59.4. Inside this category, GPQA is the benchmark that creates the most daylight between them.
Which is better for coding, Claude 3.5 Sonnet or Claude Mythos 5?
Claude Mythos 5 has the edge for coding in this comparison, averaging 89.7 versus 49. Inside this category, SWE-bench Verified is the benchmark that creates the most daylight between them.
Which is better for math, Claude 3.5 Sonnet or Claude Mythos 5?
Claude Mythos 5 has the edge for math in this comparison, averaging 97.6 versus 1.6. Claude 3.5 Sonnet stays close enough that the answer can still flip depending on your workload.
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