Chat Latest

Overview

Chat Latest is the Instant model used in ChatGPT, offered by OpenAI under the model ID openai/chat-latest. It accepts text and image input, returns text, and supports tool calling and structured output, with a context window of 400,000 tokens. It is intended for conversational use inside applications.

Chat Latest has a context window of 400,000 tokens and can generate up to 128,000 output tokens. It accepts text and image input and returns text output. Its knowledge cutoff is August 31, 2025, and it was released on May 5, 2026.

Capabilities

Chat Latest supports tool calling, structured output and image input, and it returns text. It can generate up to 128,000 output tokens per request.

Its knowledge cutoff is August 31, 2025, and cached input reads have a separate, lower price.

Pricing

Chat Latest is billed per token: $5.00 per 1M input tokens and $30.00 per 1M output tokens. Cached input reads cost $0.50 per 1M tokens. Chat Latest is available through RealRelay's OpenAI-compatible API.

Use cases

Use Chat Latest for conversational assistants built on the Instant model used in ChatGPT, answering questions about text, screenshots and photos in everyday language.

Its tool calling and structured output let an application connect the assistant to functions and return replies in a fixed format that other systems can parse.