What is GPT-4.1 Nano?

GPT-4.1 Nano is the lowest-cost long-context model in the GPT-4.1 series, optimized for extraction, tagging, and fast classification.

How good is GPT-4.1 Nano?

It delivers exceptional performance for its size, particularly in code autocompletion and fast classification pipelines.

What can GPT-4.1 Nano do?

It excels at code autocompletion, fast classification, lightweight agentic tools, real-time applications, and large document extraction.

What are GPT-4.1 Nano's limitations?

Limited deep reasoning, potential instability with fine-tuned models, and may not match larger models for complex tasks.

How much does GPT-4.1 Nano cost?

GPT-4.1 Nano pricing is $0.10 per 1M input tokens and $0.40 per 1M output tokens. Cached input tokens cost $0.025 per 1M.

LangFast

Beta

GPT-4.1 Nano

Lowest-cost long-context model for extraction and tagging.

Try in Playground

Community Sentiment

Mostly Positive

Based on Reddit reviews

Community Verdict

Best for Fast Tasks

Based on Reddit reviews

Input Modalities

Text, Images

Output Modalities

Text

Price / 1M tokens

$0.1$0.4

InputOutput

Best For

Code autocomplete & IDEs

Fast classification/reranking

Lightweight edge agents

Ultra-low-latency real-time apps

Large-context processing (1M tokens)

High-volume, cost-sensitive use

Large-doc data extraction

Avoid For

Fine-tuned models (instability)

Deep reasoning / multi-step planning

Highest-accuracy requirements

Complex problem solving

When GPT-4.1 / 4.1 Mini quality is needed

1,000,000 context window

32,768 max output tokens

Jan 1, 2024 knowledge cutoff

Reasoning not supported

Parameters

While OpenAI documents a unified parameter set for the Chat Completions and Responses APIs, each model supports only a limited subset of model-specific parameters and values. This table lists the supported model-specific GPT-4.1 Nano API parameters and allowed values.

Parameter	Description	Path	Supported Values
Model	Selects the model version for the request	model	gpt-4.1-nanogpt-4.1-nano-2025-04-14
Message roles	Defines the role of the message in the input	messages[].role	developersystemuserassistant
Max output tokens	Max output tokens the model may generate	max_completion_tokens	16 .. 32,768
Output format	Specifies the output format, including structured JSON schemas	response_format	textjson_objectjson_schema
Temperature	Controls how random or deterministic the output is	temperature	0 .. 2
Top P	Controls how diverse the output tokens are	top_p	0 .. 1
Presence penalty	Encourages the model to introduce new topics	presence_penalty	-2 .. 2
Frequency penalty	Reduces repetition of the same words or phrases	frequency_penalty	-2 .. 2
Reasoning effort	Controls the depth of internal reasoning used by the model	reasoning_effort	Not supported
Reasoning summary	Controls whether the model produces a concise or detailed reasoning summary	reasoning_summary	Not supported
Verbosity	Controls how brief or detailed the generated response is	verbosity	Not supported

Pricing

GPT-4.1 Nano API pricing is based on token usage for input and output. Prices are listed per 1M tokens, with lower rates for cached input. Tool-specific features may add per-call fees.

Text tokens

Per 1M tokens

Input$0.10

Cached input$0.03

Output$0.40

Example costs (GPT-4.1 Nano)

TASK

APPROX COST

Code autocompletion (100 tokens)

~$0.00001

Fast classification batch (10k items)

~$0.01

Large document extraction

~$0.02–$0.08

Modalities

What the model can accept and produce

TextInput and output

ImagesInput only

AudioNot supported

VideoNot supported

Features

Platform-level capabilities

StreamingSupported

Function callingSupported

Structured outputsSupported

Fine-tuningSupported

DistillationNot supported

Predicted outputsSupported

Tools

Tools supported by this model when using the Responses API.

Web searchNot supported

File searchSupported

Image generationSupported

Code interpreterSupported

MCPSupported

Computer useNot supported

Snapshots

GPT-4.1 Nano model snapshots ensure stable behavior by locking a specific version. See all available snapshots and aliases below.

gpt-4.1-nano

↪ gpt-4.1-nano-2025-04-14

gpt-4.1-nano-2025-04-14

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