Chat turn cost
1K fresh input + 500 output tokens
Claude Opus 5
Claude Opus 5 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Claude Mythos 5 vs Claude Opus 5
Updated October 20, 2026. We do not rank this pair: at least one has no public score. Public scores include evidence status and uncertainty.
Share or export
Decision reading
At least one model is not scored in the current public ranking lane, so the page does not name an overall quality winner. 5 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.
- Shared results
- 5
- Claude Mythos 5 only
- 10
- Claude Opus 5 only
- 75
- Like-for-like categories
- 0 / 8
Supported: Claude Opus 5How the comparison works
Which one for your work
Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.
Cache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
Claude Opus 5
Claude Opus 5 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-rates
Show secondary and unsupported calls
Repository review cost
50K fresh input + 3K output tokens
Claude Opus 5
Claude Opus 5 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Confidence: listed-ratesCoding work
Code generation, repair, and software-engineering tasks
Not enough matched evidence
Claude Mythos 5 is not ranked on the public lane for coding, so no winner is named for coding.
Confidence: limitedAgentic work
Tool use, computer use, and multi-step task completion
Not enough matched evidence
Claude Mythos 5 is not ranked on the public lane for agentic, so no winner is named for agentic.
Confidence: limitedLong documents
Prompts that approach the documented context limit
No clear pick
The documented context windows are equal.
Confidence: documented
Which one for a specific job
Choose a job from the LLM Selector's task catalog to see the category row it rests on, under the same basis rules as the table below. A directional row stays directional; choosing a job never creates a winner.
The same task catalog as the LLM Selector. Each job names the evidence surface it rests on; nothing here adds a new score.
—Claude Mythos 570.8Claude Opus 5
Not comparable · BenchAlign v5.8
The coding row is not comparable on the public lane: at least one model is not measured or not ranked there.
Coding scores combine specific tasks and setups. Match the editor, harness, and effort to your workflow.
Same basis rules as the category table below
What is actually comparable
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
10 Claude Mythos 5 only
5 Shared
75 Claude Opus 5 only
Shape of the matched evidence
Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.
Too few matched category axes support a radar. The ruled list below shows only shared benchmark results; positions use each benchmark’s normalized display scale when available.
BrowseCompAgentic
Normalized gap 2.8Claude Mythos 5:88%Claude Opus 5:90.8%HLE w/o toolsKnowledge
Normalized gap 2.7Claude Mythos 5:59%Claude Opus 5:56.3%SWE-bench ProCoding
Normalized gap 1.1Claude Mythos 5:80.3%Claude Opus 5:79.2%SWE-bench VerifiedCoding
Normalized gap 0.5Claude Mythos 5:95.5%Claude Opus 5:96%HLEKnowledge
Normalized gap 0.2Claude Mythos 5:64.5%Claude Opus 5:64.7%
Bars run 0–100 on each benchmark’s normalized display scale
Category results, on a stated basis
Each row shows the public-lane category score for both models: the BenchAlign v5.8 lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.
Agentic
Not comparable- Claude Mythos 5
- Not ranked
- Claude Opus 5
- 78.4
- Supported · #4/131
- Basis
- BenchAlign v5.8 lane · 4 vs 21 public rows
- Reading
- Not comparable
Coding
Not comparable- Claude Mythos 5
- Not ranked
- Claude Opus 5
- 70.8
- Supported · #9/152
- Basis
- BenchAlign v5.8 lane · 3 vs 18 public rows
- Reading
- Not comparable
Reasoning
Not comparable- Claude Mythos 5
- Not ranked
- Claude Opus 5
- 81.0
- #8/27
- Basis
- Provisional lane · 0 vs 2 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- Claude Mythos 5
- 89.7
- Unranked · 3 rankable rows
- Claude Opus 5
- 92.2
- #2/55
- Basis
- Provisional lane · 1 vs 1 weighted rows
- Reading
- Not comparable
Knowledge
Not comparable- Claude Mythos 5
- Not ranked
- Claude Opus 5
- 82.3
- Supported · #7/187
- Basis
- BenchAlign v5.8 lane · 3 vs 19 public rows
- Reading
- Not comparable
Multilingual
Not comparable- Claude Mythos 5
- Not ranked
- Claude Opus 5
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Instruction following
Not comparable- Claude Mythos 5
- Not ranked
- Claude Opus 5
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Math
Not comparable- Claude Mythos 5
- Not ranked
- Claude Opus 5
- 91.6
- Unranked · 7 rankable rows
- Basis
- Provisional lane · 1 vs 2 weighted rows
- Reading
- Not comparable
| Category | Claude Mythos 5 | Claude Opus 5 | Basis | Reading |
|---|---|---|---|---|
| Agentic | Not ranked | 78.4Supported · #4/131 | Not comparableBenchAlign v5.8 lane · 4 vs 21 public rows | Not comparable |
| Coding | Not ranked | 70.8Supported · #9/152 | Not comparableBenchAlign v5.8 lane · 3 vs 18 public rows | Not comparable |
| Reasoning | Not ranked | 81.0#8/27 | Not comparableProvisional lane · 0 vs 2 weighted rows | Not comparable |
| Multimodal | 89.7Unranked · 3 rankable rows | 92.2#2/55 | Not comparableProvisional lane · 1 vs 1 weighted rows | Not comparable |
| Knowledge | Not ranked | 82.3Supported · #7/187 | Not comparableBenchAlign v5.8 lane · 3 vs 19 public rows | Not comparable |
| Multilingual | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Instruction following | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Math | Not ranked | 91.6Unranked · 7 rankable rows | Not comparableProvisional lane · 1 vs 2 weighted rows | Not comparable |
Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign v5.8) differ from the provisional-lane categories. Unranked scores sit on the provisional lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.
Supported evidence per lane · bars run 0–100Methodology
What each workload costs
Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.
Chat turn
1K fresh input + 500 output tokens
- Claude Mythos 5
- $0.035
- Fits in one request
- Claude Opus 5
- $0.0175
- Fits in one request
Claude Opus 5 has the lower modeled cost
Costs use the listed standard API rates.
Repository review
50K fresh input + 3K output tokens
- Claude Mythos 5
- $0.65
- Fits in one request
- Claude Opus 5
- $0.325
- Fits in one request
Claude Opus 5 has the lower modeled cost
Costs use the listed standard API rates.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- Claude Mythos 5
- $0.9
- Fits in one request
- Claude Opus 5
- $0.45
- Fits in one request
Claude Opus 5 has the lower modeled cost
Costs use the listed standard API rates.
Cached input falls back to the list input rate only where a cached rate is unpublished
Specification differences
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
SpecificationClaude Mythos 5Claude Opus 5
Context window
Maximum documented context; output-token limits may be lower.
Claude Mythos 5
Claude Opus 5
API model ID
Claude Mythos 5
claude-mythos-5
Anthropic model overviewClaude Opus 5
claude-opus-5
Anthropic model overviewCached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Claude Mythos 5
$1 per 1M cached input tokens
Claude API pricingClaude Opus 5
$0.5 per 1M cached input tokens
Claude API pricingDocumented inputs
Claude Mythos 5
text, image
Anthropic model overviewClaude Opus 5
text, image
Anthropic model overviewDocumented outputs
Claude Mythos 5
Claude Opus 5
Provider availability
Claude Mythos 5
Limited Access · Claude API
Anthropic model overviewClaude Opus 5
Generally Available · Claude API
Anthropic model overviewReasoning profile
Claude Mythos 5
Reasoning
Claude Opus 5
Reasoning
Weight access
Claude Mythos 5
Proprietary
Claude Opus 5
Proprietary
License
Claude Mythos 5
Proprietary
Claude Opus 5
Proprietary
Release date
Claude Mythos 5
2026-06-09
Claude Opus 5
2026-07-24
If you already use one of these models
- Deployment change
- Both entries list Anthropic as the provider. Confirm endpoint, model ID, limits, and feature support before switching.
- Quality signal
- At least one model is not scored in the current public ranking lane, so the page does not name an overall quality winner.
- Workload cost
- Repository review: $0.65 vs $0.325. Cache-heavy agent loop: $0.9 vs $0.45.
- Context tradeoff
- Both models list 1M.
Run the same representative tasks against both endpoints before changing production traffic.
Questions
Which is better, Claude Mythos 5 or Claude Opus 5?
At least one model is not scored in the current public ranking lane, so the page does not name an overall quality winner. The page therefore keeps the decision tied to the specific documented workload.
Which is better for coding, Claude Mythos 5 or Claude Opus 5?
Claude Mythos 5 is not ranked on the public lane for coding, so no winner is named for coding.
Which is better for agentic tasks, Claude Mythos 5 or Claude Opus 5?
Claude Mythos 5 is not ranked on the public lane for agentic tasks, so no winner is named for agentic tasks.
Which costs less, Claude Mythos 5 or Claude Opus 5?
For the stated presets, chat costs $0.035 on Claude Mythos 5 and $0.0175 on Claude Opus 5; repository review costs $0.65 and $0.325; the cache-heavy agent loop costs $0.9 and $0.45. Costs use the listed standard API rates.
Which has the larger context window, Claude Mythos 5 or Claude Opus 5?
Both models list the same context window, 1M.
Benchmark evidence
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Browse raw public benchmark evidence90 rows
Agentic
Terminal-Bench 2.1
Claude Mythos 588.0%SourceClaude Opus 5—Not directly comparable
OSWorld-Verified
Claude Mythos 585%SourceClaude Opus 5—Not directly comparable
BrowseComp
Claude Mythos 588%SourceClaude Opus 590.8%SourceClaude Opus 5 leads this result
CyberGym
Claude Mythos 583.8%SourceClaude Opus 5—Not directly comparable
Terminal-Bench 3.0
Claude Mythos 5—Claude Opus 542.7%SourceNot directly comparable
HLE w/ tools
Claude Mythos 5—Claude Opus 564.7%SourceNot directly comparable
DeepSearchQA
Claude Mythos 5—Claude Opus 595.0%SourceNot directly comparable
DRACO
Claude Mythos 5—Claude Opus 588.6%SourceNot directly comparable
BrowseComp (10-agent, prerelease)
Claude Mythos 5—Claude Opus 593.6%SourceNot directly comparable
OSWorld 2.0
Claude Mythos 5—Claude Opus 570.6%SourceNot directly comparable
MCP Atlas
Claude Mythos 5—Claude Opus 585.8%SourceNot directly comparable
MCP-Atlas claim coverage
Claude Mythos 5—Claude Opus 589.1%SourceNot directly comparable
LAB all-pass (Anthropic harness)
Claude Mythos 5—Claude Opus 523.58%SourceNot directly comparable
LAB criterion-pass (Anthropic harness)
Claude Mythos 5—Claude Opus 593.74%SourceNot directly comparable
LAB all-pass (Harvey held-out)
Claude Mythos 5—Claude Opus 511.7%SourceNot directly comparable
LAB criterion-pass (Harvey held-out)
Claude Mythos 5—Claude Opus 594.1%SourceNot directly comparable
Toolathlon-Verified
Claude Mythos 5—Claude Opus 580.6%SourceNot directly comparable
Toolathlon Verified Pass@3
Claude Mythos 5—Claude Opus 587.0%SourceNot directly comparable
Toolathlon Verified Pass³
Claude Mythos 5—Claude Opus 573.1%SourceNot directly comparable
Toolathlon Verified avg. turns
Claude Mythos 5—Claude Opus 523.5 turnsSourceNot directly comparable
AutomationBench
Claude Mythos 5—Claude Opus 526.0%SourceNot directly comparable
Terminal-Bench 2.1 (Vals)
Claude Mythos 5—Claude Opus 584.6%SourceNot directly comparable
ApprenticeBench
Claude Mythos 5—Claude Opus 536%SourceNot directly comparable
MazeBench
Claude Mythos 5—Claude Opus 512%SourceNot directly comparable
Coding
SWE-bench Verified
Claude Mythos 595.5%SourceClaude Opus 596%SourceClaude Opus 5 leads this result
SWE-bench Pro
Claude Mythos 580.3%SourceClaude Opus 579.2%SourceClaude Mythos 5 leads this result
Terminal-Bench 2.1
Claude Mythos 588.0%SourceClaude Opus 5—Not directly comparable
Bug Hunt Bench
Claude Mythos 5—Claude Opus 527.0 fixesSourceNot directly comparable
SWE Multilingual
Claude Mythos 5—Claude Opus 589.5%SourceNot directly comparable
SWE Multimodal
Claude Mythos 5—Claude Opus 559.4%SourceNot directly comparable
DeepSWE
Claude Mythos 5—Claude Opus 568.8%SourceNot directly comparable
FrontierCode 1.1 Main
Claude Mythos 5—Claude Opus 553.4%SourceNot directly comparable
FrontierCode 1.1 Extended
Claude Mythos 5—Claude Opus 563.6%SourceNot directly comparable
FrontierSWE v2
Claude Mythos 5—Claude Opus 552.0%SourceNot directly comparable
ProgramBench (episode 1)
Claude Mythos 5—Claude Opus 583.0%SourceNot directly comparable
ProgramBench
Claude Mythos 5—Claude Opus 593.0%SourceNot directly comparable
CursorBench 3.2
Claude Mythos 5—Claude Opus 570.0%SourceNot directly comparable
VulcanBench v3
Claude Mythos 5—Claude Opus 587.0%SourceNot directly comparable
VulcanBench CII v1
Claude Mythos 5—Claude Opus 596.4%SourceNot directly comparable
LiveCodeBench (Vals)
Claude Mythos 5—Claude Opus 589.0%SourceNot directly comparable
SWE-bench (Vals)
Claude Mythos 5—Claude Opus 597.0%SourceNot directly comparable
CursorBench 4.0
Claude Mythos 5—Claude Opus 546.6%SourceNot directly comparable
PostTrainBench v1.1
Claude Mythos 5—Claude Opus 535.0%SourceNot directly comparable
Reasoning
Multimodal
SWE-bench Multimodal
Claude Mythos 554.9%SourceClaude Opus 5—Not directly comparable
CharXiv
Claude Mythos 593.5%SourceClaude Opus 5—Not directly comparable
CharXiv w/o tools
Claude Mythos 588.9%SourceClaude Opus 5—Not directly comparable
Chartography (no tools)
Claude Mythos 5—Claude Opus 529.6%SourceNot directly comparable
Chartography (tools)
Claude Mythos 5—Claude Opus 583.0%SourceNot directly comparable
BenchCAD Vision2Code (no tools)
Claude Mythos 5—Claude Opus 50.366SourceNot directly comparable
BenchCAD Vision2Code (tools)
Claude Mythos 5—Claude Opus 50.821SourceNot directly comparable
GDP.pdf (no tools)
Claude Mythos 5—Claude Opus 583.4%SourceNot directly comparable
GDP.pdf (tools)
Claude Mythos 5—Claude Opus 585.5%SourceNot directly comparable
OfficeQA
Claude Mythos 5—Claude Opus 578.1%SourceNot directly comparable
OfficeQA Pro
Claude Mythos 5—Claude Opus 566.9%SourceNot directly comparable
Knowledge
GPQA
Claude Mythos 594.1%SourceClaude Opus 5—Not directly comparable
HLE
Claude Mythos 564.5%SourceClaude Opus 564.7%SourceClaude Opus 5 leads this result
HLE w/o tools
Claude Mythos 559%SourceClaude Opus 556.3%SourceClaude Mythos 5 leads this result
HLE-Verified
Claude Mythos 5—Claude Opus 554.4%SourceNot directly comparable
LABBench2
Claude Mythos 5—Claude Opus 584.2%SourceNot directly comparable
HealthBench (raw)
Claude Mythos 5—Claude Opus 567.1%SourceNot directly comparable
HealthBench (length-adjusted)
Claude Mythos 5—Claude Opus 557.8%SourceNot directly comparable
HealthBench Professional
Claude Mythos 5—Claude Opus 559.8%SourceNot directly comparable
HealthBench Professional (raw)
Claude Mythos 5—Claude Opus 573.4%SourceNot directly comparable
BioMysteryBench (human-solvable)
Claude Mythos 5—Claude Opus 590.1%SourceNot directly comparable
BioMysteryBench (human-difficult)
Claude Mythos 5—Claude Opus 549.4%SourceNot directly comparable
SpatialBench Verified
Claude Mythos 5—Claude Opus 572.5%SourceNot directly comparable
SingleCellBench
Claude Mythos 5—Claude Opus 560.6%SourceNot directly comparable
ProteinGym Hard
Claude Mythos 5—Claude Opus 547.7%SourceNot directly comparable
Protein Design
Claude Mythos 5—Claude Opus 542.5%SourceNot directly comparable
Organic chemistry V2
Claude Mythos 5—Claude Opus 561.6%SourceNot directly comparable
Protocols (troubleshooting)
Claude Mythos 5—Claude Opus 561.1%SourceNot directly comparable
Protocols (understanding)
Claude Mythos 5—Claude Opus 578.4%SourceNot directly comparable
GPQA Diamond (Vals)
Claude Mythos 5—Claude Opus 593.4%SourceNot directly comparable
MMLU-Pro (Vals)
Claude Mythos 5—Claude Opus 591.6%SourceNot directly comparable
Multilingual
Instruction following
Gray Swan IPI (15 attempts)
Claude Mythos 5—Claude Opus 54.6%SourceNot directly comparable
Math
USAMO 2026
Claude Mythos 597.6%SourceClaude Opus 5—Not directly comparable
IMO 2026
Claude Mythos 5—Claude Opus 542/42SourceNot directly comparable
RiemannBench (no tools)
Claude Mythos 5—Claude Opus 560.0%SourceNot directly comparable
RiemannBench (tools)
Claude Mythos 5—Claude Opus 579.0%SourceNot directly comparable
ArXivMath Jun. 2026 (no tools)
Claude Mythos 5—Claude Opus 590.8%SourceNot directly comparable
ArXivMath Jun. 2026 (tools)
Claude Mythos 5—Claude Opus 591.3%SourceNot directly comparable
FrontierMath v2 (Tiers 1-3)
Claude Mythos 5—Claude Opus 585.614%SourceNot directly comparable
FrontierMath v2 (Tier 4)
Claude Mythos 5—Claude Opus 573.171%SourceNot directly comparable
90 public results · 5 shared
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Last updated October 20, 2026