OpenAI: GPT-4.1

openai/gpt-4.1 · OpenAINot yet established

Declared family: GPT
Evidence confidence: Unknown
Declared tokenizer tag: GPT
Entered catalogue: 14 April 2025
Last tested: Not yet measured
Measurement: Awaiting measurement

Evidence stack

Signals of different kinds, weighed together

Signal	Result	Reference
Tokenizer signature	Not measured	–
API surface	Identical contract to 2 other entries	api_9c6f5f7f
Context and output	1,047,576 context · 32,768 max output	declared
Reasoning contract	None declared	declared
Serving providers observed	None recorded yet	–

Declared record

What the catalogue claims about this model

GPT-4.1 is a flagship large language model optimized for advanced instruction following, real-world software engineering, and long-context reasoning. It supports a 1 million token context window and outperforms GPT-4o and...

Modalities: text+image+file->text
Declared tokenizer: GPT
Prompt price: $2.00 / M tokens
Completion price: $8.00 / M tokens

Supported parameters

max_completion_tokensmax_tokensresponse_formatseedstructured_outputstemperaturetool_choicetoolstop_p

defaults: {}

Catalogue entry

History

Every observation, kept as taken

14 April 2025Enters the OpenRouter catalogue declared as GPT.

Cite this page as the evidence record for OpenAI: GPT-4.1: 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.