Claude Sonnet 4.5 with Jev
Claude Sonnet 4.5 is a model from Anthropic, released 2025-09-29. It costs $3.00 per million input tokens and $15 per million output tokens, reads up to 1M tokens of context, and writes up to 64,000 tokens in one reply. Through llm11, set model to anthropic/claude-sonnet-4.5.
- Input price
- $3.00 / 1M
- Output price
- $15 / 1M
- Context window
- 1M tokens
- Max output
- 64K tokens
- Cached input
- $0.300 / 1M
- Released
- 2025-09-29
- Accepts
- text, image, file
- Intelligence index
- 20.7
Read from the provider's prompt cache
Artificial Analysis, via the catalogue
Read from the live catalogue and refreshed daily. At blended list price, 8% of the 332 priced models we can call cost more.
Using Claude Sonnet 4.5 with Jev
Jev is TypeSafe AI's System One model. It reads each request first and decides which model in your pool answers, with a calibrated confidence on that call. Claude Sonnet 4.5 does the answering when Jev sends it work, or when you name it yourself. Claude Sonnet 4.5 falls in the llm11-smart band, and the labs and limits it meets make it eligible for that pack. Packs keep a spread of eight models per band, and it is not one of the eight today, so it is only picked when you name it in a custom pool.
Jev is new, so we have not published results for Claude Sonnet 4.5 with and without it, and this page does not invent any. Every response comes with a receipt that names the model that answered and what it cost against your most expensive model, so you can measure the pairing on your own traffic.
What a request costs
List price arithmetic, the same sum a receipt does. llm11 adds nothing per request; the only fee is on buying credits.
| Request | Tokens in / out | One | A thousand |
|---|---|---|---|
| Short chat turn | 500 / 200 | $0.00450 | $4.50 |
| Question over retrieved documents | 4,000 / 500 | $0.019 | $19.50 |
| Long document summary | 30,000 / 1,000 | $0.105 | $105.00 |
Cheaper models to try
Nearest in price and below Claude Sonnet 4.5, each within a few points of it on the intelligence index.
| Model | Input / 1M | Output / 1M | Context | Index | Released |
|---|---|---|---|---|---|
| OpenAI GPT-5.6 Terra | $2.00 | $12 | 1.05M | 42.1 | |
| Google Gemini 3.1 Pro Preview | $2.00 | $12 | 1.05M | 29.7 | |
| Anthropic Claude Sonnet 5.5 | $2.00 | $10 | 1M | 56 | |
| OpenAI GPT-6 Sol | $2.00 | $10 | 1.05M | 47.5 |
Call it
Same OpenAI request shape. Naming the model pins it, so nothing is routed, and the answer is still checked.
python
from openai import OpenAI
client = OpenAI(base_url="https://www.llm11.com/v1", api_key="llm11_live_...")
res = client.chat.completions.create(
model="anthropic/claude-sonnet-4.5",
messages=[{"role": "user", "content": "Hello"}],
)More from Anthropic
| Model | Input / 1M | Output / 1M | Context | Released |
|---|---|---|---|---|
| Claude Sonnet 5.5 | $2.00 | $10 | 1M | |
| Claude Opus 5.5 | $4.00 | $20 | 1M | |
| Claude Fable 5.1 | $10 | $50 | 1M | |
| Claude Opus 5 | $5.00 | $25 | 1M | |
| Claude Sonnet 5 | $2.00 | $10 | 1M | |
| Claude Fable 5 | $10 | $50 | 1M |
Questions
- What is Claude Sonnet 4.5 with Jev?
- Jev is TypeSafe AI's System One model. It reads each request first and decides which model in your pool answers, with a calibrated confidence on that call. Claude Sonnet 4.5 does the answering when Jev sends it work, or when you name it yourself. Claude Sonnet 4.5 falls in the llm11-smart band, and the labs and limits it meets make it eligible for that pack. Packs keep a spread of eight models per band, and it is not one of the eight today, so it is only picked when you name it in a custom pool. Routing decisions are made by Jev, TypeSafe AI's System One model.
- Is Claude Sonnet 4.5 a System One model?
- No. Claude Sonnet 4.5 answers requests. The System One model is Jev, which decides which model answers each one, so the two do different jobs and llm11 uses both.
- How much does Claude Sonnet 4.5 cost?
- $3.00 per million input tokens and $15 per million output tokens. A 4,000 token prompt with a 500 token answer costs about $0.019, so a thousand of them is about $19.50. llm11 passes provider list price through and charges 5% when you buy credits.
- What is the Claude Sonnet 4.5 context window?
- 1,000,000 tokens, with up to 64,000 tokens in a single reply.
- Does Claude Sonnet 4.5 support tool calling and structured output?
- The catalogue lists tool calling, structured output and reasoning controls.
- Can I use Claude Sonnet 4.5 through llm11?
- Yes. Set model to anthropic/claude-sonnet-4.5 on the OpenAI-compatible endpoint and the request goes to it directly, with verification still running.
- Does Jev route to Claude Sonnet 4.5?
- Routing decisions are made by Jev, TypeSafe AI's System One model. Claude Sonnet 4.5 falls in the llm11-smart band, and the labs and limits it meets make it eligible for that pack. Packs keep a spread of eight models per band, and it is not one of the eight today, so it is only picked when you name it in a custom pool.
- What is a cheaper alternative to Claude Sonnet 4.5?
- Nearest in price and below it: OpenAI GPT-5.6 Terra at $2.00 in and $12 out, Google Gemini 3.1 Pro Preview at $2.00 in and $12 out and Anthropic Claude Sonnet 5.5 at $2.00 in and $10 out. Nearest in price and below Claude Sonnet 4.5, each within a few points of it on the intelligence index.