Anthropic: Claude Sonnet 4

anthropic/claude-sonnet-4 · AnthropicNot yet established
Declared family
Claude
Evidence confidence
Unknown
Declared tokenizer tag
Claude
Entered catalogue
22 May 2025
Last tested
Not yet measured
Measurement
Awaiting measurement

Evidence stack

Signals of different kinds, weighed together
SignalResultReference
Tokenizer signatureNot measured
API surfaceNo other entry shares this exact contractapi_cce6f7c3
Context and output1,000,000 context · 64,000 max outputdeclared
Reasoning contractOptionaldeclared
Serving providers observedNone recorded yet

Declared record

What the catalogue claims about this model

Claude Sonnet 4 significantly enhances the capabilities of its predecessor, Sonnet 3.7, excelling in both coding and reasoning tasks with improved precision and controllability. Achieving state-of-the-art performance on SWE-bench (72.7%),...

Modalities
text+image+file->text
Declared tokenizer
Claude
Prompt price
$3.00 / M tokens
Completion price
$15.0 / M tokens

Supported parameters

include_reasoningmax_tokensreasoningstoptemperaturetool_choicetoolstop_ktop_p

defaults: {"temperature":null,"top_p":null,"top_k":null,"frequency_penalty":null,"presence_penalty":null,"repetition_penalty":null}

Catalogue entry

History

Every observation, kept as taken
  • 22 May 2025Enters the OpenRouter catalogue declared as Claude.

Cite this page as the evidence record for Anthropic: Claude Sonnet 4: the URL is stable, measurements are dated, and revisions append to the history above. Method: tokenizer fingerprinting, v1, 50 strings. The raw data behind every figure is on the data page.