Anthropic · Frontier
Claude Sonnet 4.6 Thinking
Claude Sonnet 4.6 with extended thinking enabled for tougher coding, planning, and multi‑tool tasks. Ideal for long‑horizon agent workflows and complex problem solving.
- Reasoning
- Tools
- Vision
- Structured output
- PDF input
- Input
- Text, Images
- Output
- Text
- Reasoning effort
- low · medium · high · xhigh · max
- Discovery tier
- Frontier
Pricing
USD per 1M tokens- Input
- $3.00
- Output
- $15.00
- Cache read
- $0.30
Reference prices as published by the model provider. API example
Specifications
- Context window
- 1M
- Max output
- 128K
- Average output (7 days)
- 598 tokens
- Longer than 56% of 473 models
Side by side
Claude Sonnet 4.6 Thinking compared
Specifications, prices, speed and benchmark scores next to each other. Benchmarks below show every compared model too.
| Claude Sonnet 4.6 ThinkingAnthropicThis model | Claude Sonnet 5.5AnthropicRemove | |
|---|---|---|
| Provider | Anthropic | Anthropic |
| Discovery tier | Frontier | Frontier |
| Added | Feb 17, 2026 | Sep 28, 2026 |
| Limits | ||
| Context window | 1M | 1M |
| Max output | 128K | 128K |
| Average output | 598 tokens | 523 tokens |
| Pricing, USD per 1M tokens | ||
| Input | $3.00 | $2.00Best |
| Output | $15.00 | $10.00Best |
| Cache read | $0.30 | $0.10Best |
| Cache write | — | $2.50 |
| Performance | ||
| Throughput | 97.5 tok/s | 201.5 tok/sBest |
| Time to first token | 3.1 sBest | 5.8 s |
| Request success (24h) | 100.0%Best | 99.8% |
| Benchmark indexes | ||
| Intelligence Index | 30.1 | 46.8Best |
| Coding Index | 63.0 | — |
| Capabilities | ||
| Reasoning | Yes | Yes |
| Tools | Yes | Yes |
| Vision | Yes | Yes |
| Structured output | Yes | Yes |
| PDF input | Yes | Yes |
| Reasoning effort | low, medium, high, xhigh, max | low, medium, high |
Public evaluations
Benchmarks
Independent evaluation results, with how each score ranks among the models in the Noumen catalog.
- Claude Sonnet 4.6 Thinking
- Claude Sonnet 5.5
Intelligence Index
- Claude Sonnet 4.6 Thinking30.1
- Claude Sonnet 5.546.8
Claude Sonnet 4.6 Thinking tested at max reasoning effort
Claude Sonnet 4.6 Thinking: Better than 73% of 326 scored models
Indexes
Coding Index
Composite of the coding evaluations
- Claude Sonnet 4.6 Thinking: 63.0
- Claude Sonnet 5.5: —
Agentic work
AutomationBench-AA
Workflow automation, penalized for guardrail violations
- Claude Sonnet 4.6 Thinking: 20.1%
- Claude Sonnet 5.5: 59.4%Top
AutomationBench-AA tasks completed
Workflows finished end to end without a guardrail violation
- Claude Sonnet 4.6 Thinking: 3.7%
- Claude Sonnet 5.5: 29.4%Top
AA-Briefcasev1.1
Agentic knowledge work, rated head to head
- Claude Sonnet 4.6 Thinking: 1,062 Elo
- Claude Sonnet 5.5: 1,635 EloTop
GDPval-AAv2.1
Economically valuable occupational tasks, rated head to head
- Claude Sonnet 4.6 Thinking: 1,233 Elo
- Claude Sonnet 5.5: 1,548 EloTop
Document reasoning
GDP.pdf
Professional reasoning over PDF documents, all-pass rate
- Claude Sonnet 4.6 Thinking: 15.8%
- Claude Sonnet 5.5: 25.2%Top
AA-LCRv1.1
Reasoning across long documents
- Claude Sonnet 4.6 Thinking: 80.0%Top
- Claude Sonnet 5.5: 78.0%
MLCR-AA
Long-context reasoning over medical records
- Claude Sonnet 4.6 Thinking: 7.8%
- Claude Sonnet 5.5: 18.9%Top
Reasoning and knowledge
Humanity’s Last Exam
Expert-level questions across academic fields
- Claude Sonnet 4.6 Thinking: 33.6%
- Claude Sonnet 5.5: 45.8%Top
GPQA Diamond
Graduate-level science questions
- Claude Sonnet 4.6 Thinking: 87.5%
- Claude Sonnet 5.5: —
IFBench
Following precise output instructions
- Claude Sonnet 4.6 Thinking: 56.6%
- Claude Sonnet 5.5: —
Coding
Terminal-Benchv4.0
Practical software engineering in a terminal
- Claude Sonnet 4.6 Thinking: 3.0%
- Claude Sonnet 5.5: 43.9%Top
SciCode
Scientific computing in Python
- Claude Sonnet 4.6 Thinking: 50.1%
- Claude Sonnet 5.5: 53.7%Top
Legacy evaluations
Terminal-Bench Hard
Earlier terminal task suite
- Claude Sonnet 4.6 Thinking: 53.0%
- Claude Sonnet 5.5: —
τ²-Bench Telecom
Tool use in a customer-support simulation
- Claude Sonnet 4.6 Thinking: 75.7%
- Claude Sonnet 5.5: —
AA-LCR (unversioned)
Long-context reasoning, earlier grading
- Claude Sonnet 4.6 Thinking: 80.0%Top
- Claude Sonnet 5.5: 78.0%
Scores from Artificial Analysis, updated Oct 26, 2026. Claude Sonnet 4.6 Thinking was tested at max reasoning effort; compare scores measured at the same effort.Artificial Analysis
- Claude Sonnet 4.6 Thinking
- Claude Sonnet 5.5
| Leaderboard | Claude Sonnet 4.6 Thinking | Claude Sonnet 5.5 |
|---|---|---|
| Combined | Not in top 20 | #7 · 21.7% |
Ranks among Noumen catalog models on Combined leaderboards. Only top-20 placements are listed.
- Claude Sonnet 4.6 Thinking
- Claude Sonnet 5.5
| Leaderboard | Claude Sonnet 4.6 Thinking | Claude Sonnet 5.5 |
|---|---|---|
| FrontierCode Main | Not in top 20 | #5 · 52.1% |
| FrontierCode Extended | Not in top 20 | #4 · 64.4% |
Ranks among Noumen catalog models on FrontierCode leaderboards. Only top-20 placements are listed.FrontierCode
- Claude Sonnet 4.6 Thinking
- Claude Sonnet 5.5
| Leaderboard | Claude Sonnet 4.6 Thinking | Claude Sonnet 5.5 |
|---|---|---|
| Epoch Capabilities Index | Not in top 20 | #6 · 166.2 |
Ranks among Noumen catalog models on Epoch AI leaderboards. Only top-20 placements are listed.Epoch AI
- Claude Sonnet 4.6 Thinking
- Claude Sonnet 5.5
| Leaderboard | Claude Sonnet 4.6 Thinking | Claude Sonnet 5.5 |
|---|---|---|
| ARC-AGI-1 | Not in top 20 | #11 · 96.5% |
Ranks among Noumen catalog models on ARC Prize leaderboards. Only top-20 placements are listed.ARC Prize
- Claude Sonnet 4.6 Thinking
- Claude Sonnet 5.5
| Leaderboard | Claude Sonnet 4.6 Thinking | Claude Sonnet 5.5 |
|---|---|---|
| Game Development | Not in top 20 | #3 · 1415 |
| Website | Not in top 20 | #7 · 1322 |
| UI Component | Not in top 20 | #5 · 1372 |
| Data Visualization | Not in top 20 | #2 · 1387 |
| 3D | Not in top 20 | #6 · 1399 |
| Web Apps | Not in top 20 | #5 · 1305 |
| Mobile Apps | Not in top 20 | #3 · 1280 |
Ranks among Noumen catalog models on Design Arena leaderboards. Only top-20 placements are listed.Design Arena
- Claude Sonnet 4.6 Thinking
- Claude Sonnet 5.5
| Leaderboard | Claude Sonnet 4.6 Thinking | Claude Sonnet 5.5 |
|---|---|---|
| Usage Share | Not in top 20 | #10 · 2.1% |
Ranks among Noumen catalog models on Usage leaderboards. Only top-20 placements are listed.
Live routing data
Performance and reliability
Recent averages across requests routed for this model. Your own speed depends on prompt length, reasoning effort and load.
- Throughput
- 97.5 tok/s
- Faster than 61% of 256 models
- Time to first token
- 3.1 s
- Quicker than 50% of 256 models
- Prompt cache hits
- 83.6%
- About $0.74 per 1M input tokens with caching
- Request success (24h)
- 100.0%
- Reliable
Cache hits are the share of input tokens recently served from a prompt cache across all requests. They are not a forecast of your own hit rate.
- Healthy (98% or more)
- Degraded (90–98%)
- Down (under 90%)
- No requests
Developers
Use it through the API
Noumen’s API is OpenAI-compatible: any Chat Completions client works with a base URL and a key.
curl https://www.noumen.xyz/api/v1/chat/completions \
-H "Authorization: Bearer $NOUMEN_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "anthropic/claude-sonnet-4.6:thinking",
"reasoning_effort": "medium",
"messages": [{ "role": "user", "content": "Explain this stack trace." }]
}'import os
from openai import OpenAI
client = OpenAI(base_url="https://www.noumen.xyz/api/v1", api_key=os.environ["NOUMEN_API_KEY"])
reply = client.chat.completions.create(
model="anthropic/claude-sonnet-4.6:thinking",
messages=[{"role": "user", "content": "Explain this stack trace."}],
)
print(reply.choices[0].message.content)Anthropic
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