1M Token Context
Process massive documents and codebases with high recall and efficient memory management.
curl --request POST "https://gptproto.com/v1/chat/completions" \
--header "Authorization: Bearer $GPTPROTO_API_KEY" \
--header "Content-Type: application/json" \
--data '{
"model": "claude-sonnet-4-20250514",
"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.
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.
Process massive documents and codebases with high recall and efficient memory management.
Control reasoning depth with the effort parameter to balance speed and intelligence.
Run Python code in a sandboxed environment for advanced data analysis and math.
Reduce latency and costs by caching frequent background data and recurring instructions.
Get expert answers on Claude Sonnet 4 API performance, writing style, and technical capabilities based on real developer experiences and official documentation.
Guides, comparisons, and updates related to this model.
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