Coding work
Code generation, repair, and software-engineering tasks
Not enough matched evidence
Claude 3.5 Sonnet and Claude Opus 4.5 Thinking are not ranked on the public lane for coding, so no winner is named for coding.
Confidence: limited
Claude 3.5 Sonnet vs Claude Opus 4.5 Thinking
Updated September 29, 2026. Rank says Claude Opus 4.5 Thinking is ahead. Price, access, and your workload can each overturn that. Public scores include evidence status and uncertainty.
Both of these models will change. Get the price, version and retirement notices for the pair, each with its source. Follow model changes
Share or export
Decision reading
The public evidence has no benchmark result shared by both models, so it does not support a quality verdict. Use the documented cost, context, and runtime rows instead. 0 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.
- Shared results
- 0
- Claude 3.5 Sonnet only
- 4
- Claude Opus 4.5 Thinking only
- 1
- Like-for-like categories
- 0 / 8
Estimated: Claude 3.5 Sonnet and Claude Opus 4.5 ThinkingHow 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.
No workload recommendation clears the current evidence threshold.
Use the matched evidence, workload costs, and sourced specifications below instead of treating a point score as a universal answer.
Show secondary and unsupported calls
Agentic work
Tool use, computer use, and multi-step task completion
Not enough matched evidence
Claude 3.5 Sonnet and Claude Opus 4.5 Thinking are 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: documentedChat turn cost
1K fresh input + 500 output tokens
Not enough matched evidence
A complete comparable API-rate estimate is not available for both models.
Confidence: listed-ratesCache-heavy agent loop cost
200K cached + 20K fresh input + 10K output tokens
Not enough matched evidence
The page does not recommend a cost winner because at least one model cannot fit the stated workload in one request. Claude 3.5 Sonnet does not fit this workload in one request. Claude Opus 4.5 Thinking does not fit this workload in one request. Claude 3.5 Sonnet has no published cached-input rate, so cached tokens use its listed input rate. Claude Opus 4.5 Thinking has no comparable published API token rate.
Confidence: rate-fallbackRepository review cost
50K fresh input + 3K output tokens
Not enough matched evidence
A complete comparable API-rate estimate is not available for both models.
Confidence: listed-rates
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 3.5 Sonnet—Claude Opus 4.5 Thinking
Not comparable · BenchAlign v5.7
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.
4 Claude 3.5 Sonnet only
1 Claude Opus 4.5 Thinking 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.
A shared-evidence shape is not available.
BenchLM does not draw a radar or infer missing axes when the matched evidence is too sparse.
Category results, on a stated basis
Each row shows the public-lane category score for both models: the BenchAlign v5.7 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 3.5 Sonnet
- Not ranked
- Claude Opus 4.5 Thinking
- Not ranked
- Basis
- BenchAlign v5.7 lane · 0 vs 0 public rows
- Reading
- Not comparable
Coding
Not comparable- Claude 3.5 Sonnet
- Not ranked
- Claude Opus 4.5 Thinking
- Not ranked
- Basis
- BenchAlign v5.7 lane · 1 vs 1 public rows
- Reading
- Not comparable
Reasoning
Not comparable- Claude 3.5 Sonnet
- Not ranked
- Claude Opus 4.5 Thinking
- 75.5
- Unranked · 2 rankable rows
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Multimodal
Not comparable- Claude 3.5 Sonnet
- Not ranked
- Claude Opus 4.5 Thinking
- 70.1
- Unranked · 1 rankable row
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Knowledge
Not comparable- Claude 3.5 Sonnet
- Not ranked
- Claude Opus 4.5 Thinking
- 53.6
- Estimated · #51/169
- Basis
- BenchAlign v5.7 lane · 1 vs 0 public rows
- Reading
- Not comparable
Multilingual
Not comparable- Claude 3.5 Sonnet
- Not ranked
- Claude Opus 4.5 Thinking
- Not ranked
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Instruction following
Not comparable- Claude 3.5 Sonnet
- Not ranked
- Claude Opus 4.5 Thinking
- 68.5
- #66/124
- Basis
- Provisional lane · 0 vs 0 weighted rows
- Reading
- Not comparable
Math
Not comparable- Claude 3.5 Sonnet
- 25.6
- Unranked · 2 rankable rows
- Claude Opus 4.5 Thinking
- Not ranked
- Basis
- Provisional lane · 2 vs 0 weighted rows
- Reading
- Not comparable
| Category | Claude 3.5 Sonnet | Claude Opus 4.5 Thinking | Basis | Reading |
|---|---|---|---|---|
| Agentic | Not ranked | Not ranked | Not comparableBenchAlign v5.7 lane · 0 vs 0 public rows | Not comparable |
| Coding | Not ranked | Not ranked | Not comparableBenchAlign v5.7 lane · 1 vs 1 public rows | Not comparable |
| Reasoning | Not ranked | 75.5Unranked · 2 rankable rows | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multimodal | Not ranked | 70.1Unranked · 1 rankable row | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Knowledge | Not ranked | 53.6Estimated · #51/169 | Not comparableBenchAlign v5.7 lane · 1 vs 0 public rows | Not comparable |
| Multilingual | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Instruction following | Not ranked | 68.5#66/124 | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Math | 25.6Unranked · 2 rankable rows | Not ranked | Not comparableProvisional lane · 2 vs 0 weighted rows | Not comparable |
Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign v5.7) 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.
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 3.5 Sonnet
- $0.0105
- Fits in one request
- Claude Opus 4.5 Thinking
- API rate not published
- Fits in one request
Claude Opus 4.5 Thinking has no comparable published API token rate.
Repository review
50K fresh input + 3K output tokens
- Claude 3.5 Sonnet
- $0.195
- Fits in one request
- Claude Opus 4.5 Thinking
- API rate not published
- Fits in one request
Claude Opus 4.5 Thinking has no comparable published API token rate.
Cache-heavy agent loop
200K cached + 20K fresh input + 10K output tokens
- Claude 3.5 Sonnet
- $0.81
- Does not fit in one request
- Cached input priced at the published list-input rate
- Claude Opus 4.5 Thinking
- API rate not published
- Does not fit in one request
- Cached-input rate unavailable
Claude 3.5 Sonnet does not fit this workload in one request. Claude Opus 4.5 Thinking does not fit this workload in one request. Claude 3.5 Sonnet has no published cached-input rate, so cached tokens use its listed input rate. Claude Opus 4.5 Thinking has no comparable published API token rate.
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 3.5 SonnetClaude Opus 4.5 Thinking
Context window
Maximum documented context; output-token limits may be lower.
Claude 3.5 Sonnet
200K
Claude Opus 4.5 Thinking
200K
API model ID
Claude 3.5 Sonnet
Not sourced
Claude Opus 4.5 Thinking
Not sourced
Cached-input rate
A missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
Claude 3.5 Sonnet
Not published
Claude Opus 4.5 Thinking
No comparable hosted API rate
Documented inputs
Claude 3.5 Sonnet
Not sourced
Claude Opus 4.5 Thinking
Not sourced
Documented outputs
Claude 3.5 Sonnet
Not sourced
Claude Opus 4.5 Thinking
Not sourced
Provider availability
Claude 3.5 Sonnet
Not sourced
Claude Opus 4.5 Thinking
Not sourced
Reasoning profile
Claude 3.5 Sonnet
Non-Reasoning
Claude Opus 4.5 Thinking
Reasoning
Weight access
Claude 3.5 Sonnet
Proprietary
Claude Opus 4.5 Thinking
Proprietary
License
Claude 3.5 Sonnet
Proprietary
Claude Opus 4.5 Thinking
Proprietary
Release date
Claude 3.5 Sonnet
2024-06-01
Claude Opus 4.5 Thinking
2025-11-01
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
- The public evidence has no benchmark result shared by both models, so it does not support a quality verdict.
- Workload cost
- A complete comparable API-rate estimate is not available for both models.
- Context tradeoff
- Both models list 200K.
Run the same representative tasks against both endpoints before changing production traffic.
Questions
Which is better, Claude 3.5 Sonnet or Claude Opus 4.5 Thinking?
The public evidence has no benchmark result shared by both models, so it does not support a quality verdict. The page therefore keeps the decision tied to the specific documented workload.
Which is better for coding, Claude 3.5 Sonnet or Claude Opus 4.5 Thinking?
Claude 3.5 Sonnet and Claude Opus 4.5 Thinking are not ranked on the public lane for coding, so no winner is named for coding.
Which is better for agentic tasks, Claude 3.5 Sonnet or Claude Opus 4.5 Thinking?
Claude 3.5 Sonnet and Claude Opus 4.5 Thinking are not ranked on the public lane for agentic tasks, so no winner is named for agentic tasks.
Which costs less, Claude 3.5 Sonnet or Claude Opus 4.5 Thinking?
Both models do not have comparable published API token rates, so this page does not name a universal price winner.
Which has the larger context window, Claude 3.5 Sonnet or Claude Opus 4.5 Thinking?
Both models list the same context window, 200K.
Benchmark evidence
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
Browse raw public benchmark evidence5 rows
Coding
Knowledge
GPQA
Claude 3.5 Sonnet59.4%SourceClaude Opus 4.5 Thinking—Not directly comparable
Math
5 public results · 0 shared
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Last updated September 29, 2026