Claude Sonnet 4.5: API Pricing, Context Window & Benchmarks
Claude Sonnet 4.5 is a language model from Anthropic, released in September 2025, with multimodal input, a 200K-token context window, and pricing from $3.00/M input and $15.00/M output.
Claude Sonnet 4.5 is the best coding model in the world. It's the strongest model for building complex agents. It’s the best model at using computers. And it shows substantial gains in reasoning and math. Highest intelligence across most
Claude Sonnet 4.5 benchmarks
Rankings
Quality Tracker
Claude Sonnet 4.5 Performance Across Datasets
Scores sourced from the model's scorecard, paper, or official blog posts
llm-stats.com - Tue Jul 21 2026Claude Sonnet 4.5 pricing
Providers
Claude Sonnet 4.5 starts at $3.00 per million input tokens and $15.00 per million output tokens via Anthropic.
| Provider | Input $/M | Output $/M | Context in / out | TTFT p50 / p95 s | Output avg / p5 c/s | Success 7d | Modalities in / out |
|---|---|---|---|---|---|---|---|
 Anthropic | $3.00 | $15.00 | 200.0K/64.0K | 1.63/2.49 | 122/5 | 94.74%(38) | / |
Cached input is the discounted price for prompt tokens served from a provider cache. TTFT is time to first token. Output is characters per second; p5 is the sustained floor exceeded by 95% of observed requests. Success is calculated from completed versus failed requests over the trailing seven days.
Claude Sonnet 4.5 context window
Input and output token limits for Claude Sonnet 4.5, plus how it ranks on long-context understanding.
Claude Sonnet 4.5 API
Run a request to see the response
Use it in your code
Billed at $3.00 input / $15.00 output per 1M tokens through the LLM Stats gateway.
from openai import OpenAI
client = OpenAI(
api_key="YOUR_API_KEY",
base_url="https://gateway.llm-stats.com/v1"
)
response = client.chat.completions.create(
model="claude-sonnet-4-5-20250929",
messages=[
{"role": "user", "content": "What is machine learning?"}
]
)
print(response.choices[0].message.content)Need an API key? Create one above in the playground, or read the API documentation.
Claude Sonnet 4.5 latency
Claude Sonnet 4.5 time to first token, sustained output throughput, and failed-request rate from live API traffic over the trailing 7 days.
Provider operational metrics
Time to first token, output throughput, and failed-request rate from live API traffic
Claude Sonnet 4.5 examples
Recent arena outputs from Claude Sonnet 4.5, picked from the highest-ranked matchups.
Claude Sonnet 4.5 license
Claude Sonnet 4.5 is a proprietary model available under its provider's product and API terms, has a knowledge cutoff of January 2025.
- License
- Proprietary
- Hosted access
- Knowledge cutoff
- January 2025
Proprietary license - usage restrictions apply
Claude Sonnet 4.5 resources
Official sources for Claude Sonnet 4.5: api documentation, official playground, official launch post.
Claude Sonnet 4.5 vs other models
The most-compared alternatives to Claude Sonnet 4.5 are Grok-3 Mini, Step3-VL-10B, ERNIE 5.0. Open any pair side-by-side for benchmarks, pricing, context, and latency.
Models like Claude Sonnet 4.5
Models ranked just above and below Claude Sonnet 4.5 by LLM Stats score.
FAQ
Common questions about Claude Sonnet 4.5.