Anthropic: Claude Opus 4

anthropic/claude-opus-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_ef0b5b0d
Context and output200,000 context · 32,000 max outputdeclared
Reasoning contractOptionaldeclared
Serving providers observedNone recorded yet

Declared record

What the catalogue claims about this model

Claude Opus 4 is benchmarked as the world’s best coding model, at time of release, bringing sustained performance on complex, long-running tasks and agent workflows. It sets new benchmarks in...

Modalities
text+image+file->text
Declared tokenizer
Claude
Prompt price
$15.0 / M tokens
Completion price
$75.0 / M tokens

Supported parameters

include_reasoningmax_tokensreasoningstoptemperaturetool_choicetoolstop_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 Opus 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.