Is GPT-5 Nano available on FastMetal?

Not at the moment. GPT-5.6 Sol, from the same lab, is available on the FastMetal API today.

What is the context window of GPT-5 Nano?

400,000 tokens, shared between the prompt and the response.

How does GPT-5 Nano rank?

#220 on the public arena's Overall board (ELO 1,337). Ranks move as the leaderboard is updated.

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openai/gpt-5-nano

Not Available

GPT-5 Nano

GPT-5-Nano is the smallest and fastest variant in the GPT-5 system, optimized for developer tools, rapid interactions, and ultra-low latency environments. While limited in reasoning depth compared to its larger counterparts, it retains key instruction-following and safety features. It is the successor to GPT-4.1-nano and offers a lightweight option for cost-sensitive or real-time applications.

8/7/2025

400,000 tokens

#103 Vision (Overall)

Specifications

Modalities

Input

text

image

file

Output

text

Supported Parameters

include_reasoning

max_tokens

reasoning

response_format

seed

structured_outputs

tool_choice

tools

Max Output Tokens

128,000

Reasoning Configuration

Default: Thinking on (effort: medium)
Selectable effort levels: high
medium
low
minimal
Turning thinking off: Not possible (always thinks)

How to control thinking, and what it costs

Frequently asked questions

Is GPT-5 Nano available on FastMetal?: Not at the moment. GPT-5.6 Sol, from the same lab, is available on the FastMetal API today.
What is the context window of GPT-5 Nano?: 400,000 tokens, shared between the prompt and the response.
How does GPT-5 Nano rank?: #220 on the public arena's Overall board (ELO 1,337). Ranks move as the leaderboard is updated.