curl --request POST "https://gptproto.com/v1/chat/completions" \
--header "Authorization: Bearer $GPTPROTO_API_KEY" \
--header "Content-Type: application/json" \
--data '{
"model": "claude-sonnet-4-5-20250929-thinking",
"messages": [
{
"role": "user",
"content": "Hello"
}
]
}'Chat, coding agents & document work. Priced per 1M tokens — input, cached input and output are billed separately. GPTProto is 10% below official rates.
Claude · ≈ 148M tokens/mo (48M cached)
OpenRouter costs include its ~5.5% credit purchase fee. GPTProto applies a per-model discount (10–30% off) and your bonus credits are also spent at discounted rates — savings compound. Estimates assume a 60% cache hit rate.
| Model | Input → Output | ||||
|---|---|---|---|---|---|
| 1M | $2.70 / $14.40 per 1M | $3.38 / $0.27 per 1M | Input: TextInput: Document Output: Text | |
| — | — | $0.30 / $1.20 per 1M | — / $0.006 per 1M | Input: TextInput: Image Output: Text | |
| 1.05M | $0.79 / $2.38 per 1M | — / $0.04 per 1M | Input: Text Output: Text | ||
| 1.05M | $8.00 / $40.00 per 1M | $10.00 / $0.80 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 1.05M | $0.90 / $4.50 per 1M | $0.60 / $0.09 per 1M | Input: TextInput: ImageInput: VideoInput: DocumentInput: Audio Output: Text | ||
| 1M | $9.00 / $45.00 per 1M | $11.25 / $0.23 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 1M | $1.80 / $5.40 per 1M | $2.25 / $0.23 per 1M | Input: TextInput: ImageInput: VideoInput: DocumentInput: Audio Output: Text | ||
| — | 1.31M | $0.15 / $0.50 per 1M | — / $0.03 per 1M | Input: TextInput: ImageInput: VideoInput: Document Output: Text | |
| — | 1.05M | $0.30 / $1.20 per 1M | — / $0.006 per 1M | Input: TextInput: Image Output: Text | |
| 1.31M | $1.26 / $3.96 per 1M | — / $0.23 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 1.05M | $0.90 / $4.50 per 1M | $0.60 / $0.09 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 500K | $1.20 / $3.60 per 1M | — / $0.30 per 1M | Input: TextInput: Image Output: Text | ||
| 1M | $1.80 / $5.40 per 1M | $2.25 / $0.23 per 1M | Input: TextInput: ImageInput: VideoInput: Document Output: Text | ||
| 1M | $4.50 / $22.50 per 1M | $5.63 / $0.45 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 1.05M | $0.90 / $4.50 per 1M | $0.60 / $0.09 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 1.05M | $2.70 / $13.50 per 1M | $0.27 / $0.27 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 1.05M | $0.16 / $0.96 per 1M | $0.20 / $0.02 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 1.05M | $1.60 / $9.60 per 1M | $2.00 / $0.16 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 500K | $1.20 / $3.60 per 1M | $0.30 / $0.30 per 1M | Input: TextInput: Image Output: Text | ||
| 1M | $1.80 / $9.00 per 1M | $2.25 / $0.18 per 1M | Input: TextInput: Document Output: Text | ||
| 1.05M | $0.48 / $0.96 per 1M | $0.10 / $0.10 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 1.05M | $1.26 / $3.96 per 1M | $0.23 / $0.23 per 1M | Input: TextInput: ImageInput: Document Output: Text | ||
| 1M | $9.00 / $45.00 per 1M | $11.25 / $0.90 per 1M | Input: TextInput: Document Output: Text | ||
| 1M | $0.36 / $1.44 per 1M | $0.07 / $0.07 per 1M | Input: TextInput: Document Output: Text | ||
| 1M | $4.50 / $22.50 per 1M | $5.63 / $0.45 per 1M | Input: TextInput: Document Output: Text | ||
| 1M | $4.50 / $22.50 per 1M | $5.63 / $0.45 per 1M | Input: TextInput: Document Output: Text | ||
| — | 1.05M | $0.30 / $1.20 per 1M | — / $0.006 per 1M | Input: Text Output: Text | |
| 1M | $0.75 / $1.50 per 1M | $0.12 / $0.12 per 1M | Input: TextInput: Image Output: Text | ||
| 262K | $0.85 / $3.60 per 1M | $0.14 / $0.14 per 1M | Input: TextInput: Document Output: Text | ||
| 205K | $0.24 / $0.96 per 1M | $0.30 / $0.02 per 1M | Input: TextInput: Document Output: Text | ||
| 262K | $0.54 / $2.70 per 1M | $0.09 / $0.09 per 1M | Input: TextInput: Document Output: Text | ||
| 262K | $0.10 / $0.97 per 1M | — | Input: TextInput: Image Output: Text | ||
| 262K | $0.10 / $0.97 per 1M | — | Input: TextInput: Image Output: Text | ||
| 262K | $0.02 / $0.18 per 1M | — | Input: TextInput: Image Output: Text |
Unlock Claude Sonnet 4.5 Thinking API: The Ultimate Integration on GPT Proto
Welcome to the future of cognitive computing. The claude-sonnet-4-5-20250929-thinking model represents the pinnacle of Anthropic's reasoning capabilities, now fully accessible through the robust GPT Proto ecosystem. Whether you are building complex analytical tools or creative writing assistants, this model offers a depth of understanding that was previously unimaginable. To get started and see how this fits into your tech stack, feel free to browse all models available on our platform and discover the perfect fit for your next big project.
Mastering Logical Reasoning with Claude Sonnet 4.5 Thinking on GPT Proto
The claude-sonnet-4-5-20250929-thinking model is not just another incremental update; it is a paradigm shift in how AI handles complex, multi-step instructions. By utilizing a specialized "thinking" process, the model can deliberate on a problem before providing an answer, significantly reducing hallucinations and improving the accuracy of logical deductions. When you leverage this power on GPT Proto, you gain the advantage of a unified interface that simplifies the complexity of high-end AI. We have optimized our infrastructure to ensure that the increased latency naturally associated with "thinking" steps is managed efficiently, providing you with a smooth and responsive text-to-text experience. This makes Claude on GPT Proto the preferred choice for developers who prioritize quality and depth over superficial speed.
Tackle Complex Scientific Research and Data Synthesis with High Precision
For researchers and data analysts, the ability of Claude Sonnet 4.5 Thinking to synthesize vast amounts of information while maintaining a consistent logical thread is invaluable. On GPT Proto, you can feed the model complex datasets or long-form academic papers, and it will apply its enhanced reasoning to extract insights that other models might overlook. The "thinking" capability allows it to cross-reference facts within its internal logic chain, ensuring that the final output is not only coherent but also factually robust. This makes it an ideal partner for literature reviews, hypothesis generation, and technical documentation where precision is non-negotiable.
Revolutionize Software Engineering through Deep Chain-of-Thought Logic
Coding is more than just syntax; it is about architecture and logic. The claude-sonnet-4-5-20250929-thinking model excels at debugging and refactoring because it "thinks" through the execution flow of your code before suggesting changes. By integrating this model via GPT Proto, software teams can automate the code review process with a tool that understands the intent behind the code. It can identify edge cases that traditional LLMs might miss, suggesting optimizations that improve both performance and readability. On GPT Proto, you get the stability needed to run these intensive tasks without worrying about session timeouts or inconsistent API behavior.
"GPT Proto provides the most reliable bridge to the world's most intelligent reasoning models, ensuring your business stays ahead of the curve."
Seamless API Integration and Robust Infrastructure on GPT Proto
Integration is often the biggest hurdle when adopting new technology, but GPT Proto removes this barrier entirely. Our platform provides a standardized gateway that makes deploying the claude-sonnet-4-5-20250929-thinking model straightforward and reliable. You don't need to worry about the underlying complexities of managing different vendor protocols; our unified system handles it all. For detailed technical specifications and step-by-step guides on how to make your first call to this advanced model, please refer to our comprehensive API documentation. We focus on providing high uptime and low-latency routing, so your applications remain performant even when utilizing the most compute-heavy "thinking" models on GPT Proto.
| Feature | Standard Models | Claude Sonnet 4.5 Thinking on GPT Proto |
|---|---|---|
| Reasoning Depth | Surface-level pattern matching | Deep chain-of-thought deliberation |
| Accuracy Rate | High (subject to hallucinations) | Exceptional (verified logical paths) |
| Integration Effort | Complex multi-vendor setups | One-click access via GPT Proto API |
| Billing Model | Often confusing credit systems | Transparent direct fund balance |
Transparent Pricing and Simplified Usage Management for Global Teams
At GPT Proto, we believe that accessing cutting-edge AI should be as simple as it is powerful. That is why we have moved away from confusing credit-based systems. Instead, we use a transparent "Direct Funds" approach. You can easily top-up balance in your account using your preferred currency, and you only pay for exactly what you use. This model is perfect for teams that need to manage budgets across multiple projects. To keep an eye on your consumption in real-time, you can visit your personal dashboard, which provides granular insights into your usage patterns for the claude-sonnet-4-5-20250929-thinking model and beyond.
As the AI landscape continues to evolve, staying informed is key to maintaining a competitive edge. We regularly publish updates on model performance, optimization tips, and industry trends. We encourage you to follow our official blog to stay updated on the latest developments in the world of Claude and AI integration. Start your journey with the most advanced thinking model today on GPT Proto, and transform the way your business processes information.
Frequently Asked Questions
Common questions about claude-sonnet-4-5-20250929-thinking/text-to-text
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