Adaptive Thinking
Control reasoning depth with the effort parameter to balance speed and intelligence.
claude-sonnet-4-20250514
Claude Sonnet 4 API offers 1M token context and advanced reasoning. While it excels at coding and context management, users note its concise style and penchant for em-dashes. Perfect for technical tasks needing Opus-level depth and speed.
$ 2.4
$ 3
text
$ 12
$ 15
text
API
Text To Text
curl --location 'https://gptproto.com/v1/messages' \
--header 'Authorization: GPTPROTO_API_KEY' \
--header 'Content-Type: application/json' \
--header 'anthropic-version: 2023-06-01' \
--data '{
"model": "claude-sonnet-4-20250514",
"max_tokens": 1024,
"messages": [
{
"role": "user",
"content": "Who are you?"
}
]
}'
Claude Sonnet 4 API Advanced Features
Discover the technical capabilities that set the Claude Sonnet 4 API apart, from its massive context window to its integrated tools for web searching and code execution.
Code Execution
Run Python code in a sandboxed environment for advanced data analysis and math.
Prompt Caching
Reduce latency and costs by caching frequent background data and recurring instructions.
1M Token Context
Process massive documents and codebases with high recall and efficient memory management.
Build with claude sonnet 4.20250514 in Minutes
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Sign up
Create your free GPT Proto account to begin. You can set up an organization for your team at any time.
Top up
Your balance can be used across all models on the platform, including claude sonnet 4.20250514, giving you the flexibility to experiment and scale as needed.
Generate your API key
In your dashboard, create an API key — you'll need it to authenticate when making requests to claude sonnet 4.20250514.
Make your first API call
Use your API key with our sample code to send a request to claude sonnet 4.20250514 via GPT Proto and see instant AI-powered results.
Claude Sonnet 4 API: Common User Questions
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