GPT-6 Astra (Reasoning)

by OpenAI

GPT-6 Astra (Reasoning) is a reasoning model from OpenAI, released on September 4, 2026. It has a 1.1M-token context window and can generate up to 128K output tokens. API pricing is $10 per 1M input tokens and $50 per 1M output tokens. It ranks #3 of 220 models by Intelligence Score with a score of 58.2.

GPT-6 Astra is OpenAI's released flagship for the hardest end-to-end work across complex reasoning, coding, computer use, research, and document creation. The API model id is gpt-6-astra. It accepts text and image input with text output, supports low, medium, high, xhigh, and max reasoning effort (but not none), and provides a 1,050,000-token context window with up to 128,000 output tokens. Responses API tools include web and file search, image generation, code interpreter, hosted shell, apply patch, skills, computer use, MCP, and tool search; it also supports streaming, function calling, structured outputs, async tool calling, mid-turn steering, and configuration updates during a conversation. Standard pricing is $10 input, $1 cached input, $12.50 cache writes, and $50 output per million tokens. Requests above 272K input tokens cost 2x for input and cache and 1.5x for output across the full request; Batch and Flex are 50% of Standard, while Fast is 2x.

Key specs

ProviderOpenAI
Release date2026-09-04
Licenseproprietary
Context window1.1M tokens
Max output128K tokens
Input price$10 / 1M tokens
Output price$50 / 1M tokens
Intelligence Score58.2
Coding index47.8
Output speed122 tokens/s
Time to first token3.63 s

Quick answers

What is the context window of GPT-6 Astra (Reasoning)?

GPT-6 Astra (Reasoning) has a context window of 1.1M tokens, with a maximum output of 128K tokens per response.

How much does GPT-6 Astra (Reasoning) cost?

GPT-6 Astra (Reasoning) costs $10 per 1M input tokens and $50 per 1M output tokens through the API.

Is GPT-6 Astra (Reasoning) open source?

No. GPT-6 Astra (Reasoning) is a proprietary model from OpenAI (proprietary license).

When was GPT-6 Astra (Reasoning) released?

OpenAI released GPT-6 Astra (Reasoning) on September 4, 2026.

How does GPT-6 Astra (Reasoning) compare to Claude Opus 5.5 (Reasoning)?

GPT-6 Astra (Reasoning) scores 58.2 on the Intelligence Score versus 60.5 for Claude Opus 5.5 (Reasoning), the current #1. Input pricing is $10 vs $4 per 1M tokens.

Compare on the AI leaderboard · All AI models

More models from OpenAI