GPT-5.3 Chat

Reasoning Tool Calling Attachments Structured Output

Chat-tuned GPT model for conversational assistance, writing, and tool workflows

Providers 2

Released Mar 18, 2026

Input Modalities text, image

Output Modalities text

Tarsk Use coding

Available Providers (2)

Provider	Model ID	Input Cost	Output Cost	Context	Max Output	Docs
Requesty	`gpt-5.3-chat`	$1.57/MTok	$12.60/MTok	128K	16.4K
ZenMux	`openai/gpt-5.3-chat`	$1.75/MTok	$14/MTok	128K	16.4K

Reasoning

Tool Calling

Attachments

Open Weights

Structured Output