OpenAI: GPT-5 Image

openai/gpt-5-image

GPT-5 Image combines OpenAI's GPT-5 model with state-of-the-art image generation capabilities. It offers major improvements in reasoning, code quality, and user e...

vision

MODALITIES

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INPUT PRICE

$10per 1M

OUTPUT PRICE

$10per 1M

CONTEXT

400K

RELEASED

Oct 14, 2025

Provider				Cache	Uptime	Chat
FastAPI	—	$10	$10	Cache read$1.25

Capabilities

Input modalities

fileimagetext

Output modalities

imagetext

Features

frequency_penaltyinclude_reasoninglogit_biaslogprobsmax_tokenspresence_penaltyreasoningresponse_formatseedstopstructured_outputstemperaturetop_logprobstop_p

Get your API key

Create an API key from the Keys page, then set it as an environment variable:

export ONLIST_API_KEY=sk-...

Make your first request

Endpoints

POSThttps://onlist.io/v1/images/generations

Request Headers

Authorization:Bearer $ONLIST_API_KEY

Content-Type:application/json

Model:openai/gpt-5-image

Code samples

curl https://onlist.io/v1/images/generations \
  -H "Authorization: Bearer $ONLIST_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
       "model": "openai/gpt-5-image",
       "prompt": "A white siamese cat",
       "n": 1,
       "size": "1024x1024"
     }'

Replace $ONLIST_API_KEY with the API key from your Keys page.

Authentication

All requests must include an Authorization: Bearer <TOKEN> header. Generate keys from the Keys page; keys can be scoped to specific models, groups, IP ranges, and rate limits.

Supported parameters

Name	Type	Description
`frequency_penalty`	number	Penalizes new tokens based on their existing frequency in the text (-2.0 to 2.0).
`include_reasoning`
`logit_bias`
`logprobs`	boolean	Whether to return log probabilities of the output tokens.
`max_tokens`	integer	Maximum number of tokens to generate in the completion.
`presence_penalty`	number	Penalizes new tokens based on whether they appear in the text so far (-2.0 to 2.0).
`reasoning`
`response_format`	object	Specifies the output format. Use {"type": "json_object"} for JSON mode.
`seed`	integer	If specified, the system will attempt deterministic sampling for reproducible results.
`stop`	string \| array	Up to 4 sequences where the API will stop generating tokens.
`structured_outputs`
`temperature`	number	Sampling temperature between 0 and 2. Higher values make output more random.
`top_logprobs`	integer	Number of most likely tokens to return at each position (0-20). Requires logprobs: true.
`top_p`	number	Nucleus sampling. The model considers tokens with top_p probability mass.

These are the request parameters this model accepts. Parameter semantics follow the OpenAI Chat Completions specification.