GPT-6.1 Sol

OpenAI · GPT-6

OpenAI released GPT-6.1 Sol on September 29, 2026.

GPT-6.1 Sol is the OpenAI model released on September 29, 2026 for complex coding and professional work at a lower cost than GPT-6 Astra. It is available in the Responses and Chat Completions APIs and reached Codex and ChatGPT Work the same day. Standard pricing for prompts up to 272K input tokens is $2 per million input tokens, $0.10 cached input, $2.50 cache write and $10 output. It supports Multi-agent in beta, letting the model delegate work to subagents in a Responses API request, and OpenAI recommends the Responses API for tool calling. Ultrafast mode for GPT-6.1 Sol followed on October 8.

GPT-6.1 Sol at a glance

Released
API model id
gpt-6.1-sol
Available on
OpenAI APICodexChatGPT Work
Previous model
GPT-6 Sol (September 22, 2026)
Announcement
developers.openai.com

What changed from GPT-6 Sol

Compared with GPT-6 Sol, input and output prices are unchanged but cached input halves to $0.10 per million tokens, with a separate $2.50 cache write price. GPT-6.1 Sol also adds Multi-agent in beta.

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GPT-6.1 Sol release timeline

The launch and every later OpenAI release that mentions GPT-6.1 Sol, oldest first.

  • Released GPT-6.1 Sol (gpt-6.1-sol)

    Released GPT-6.1 Sol (gpt-6.1-sol) for complex coding and professional work at a lower cost than GPT-6 Astra. Standard pricing per 1M tokens for prompts with up to 272K input tokens is $2 input, $0.10 cached input, $2.50 cache write, and $10 output. GPT-6.1 Sol also supports Mul…

    Source: OpenAI API Changelog
  • GPT-6.1 Sol in Codex and ChatGPT Work

    GPT-6.1 Sol offers near-Astra performance for complex work at a lower cost than Astra. Use gpt-6.1-sol; it is also the default model in the bundled catalog and Amazon Bedrock catalogs as of Codex CLI 0.159.1. Availability depends on plan, client and workspace settings.

    Source: Codex Changelog
  • Ultrafast mode for GPT-6.1 Sol

    Added Ultrafast mode for GPT-6.1 Sol in the Responses API. Use gpt-6.1-sol with service_tier: "ultrafast" to reduce the time between generated output tokens. It is available to all API users, subject to rate limits, with global processing and US and EU data residency. See Ultraf…

    Source: OpenAI API Changelog

GPT-6.1 Sol FAQ

When was GPT-6.1 Sol released?

OpenAI released GPT-6.1 Sol on September 29, 2026. The launch entry below links to the official announcement.

Where is GPT-6.1 Sol available?

GPT-6.1 Sol is available on OpenAI API, Codex and ChatGPT Work. Later availability changes are listed under follow-up releases on this page.

What is the GPT-6.1 Sol API model id?

Use gpt-6.1-sol in OpenAI's API.

What came before GPT-6.1 Sol?

GPT-6.1 Sol follows GPT-6 Sol, released on September 22, 2026.

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