GPT-6 Astra
OpenAI’s GPT-6 generation. Astra (API id gpt-6-astra, 2026-09-03) is the peak for computer use, coding agents, professional artifacts, science, and cybersecurity-adjacent defender workflows. GPT-6.1 Sol (gpt-6.1-sol, 2026-09-29) is the current lower-cost Sol for complex coding and professional work at the same $2/$10 list price as GPT-6 Sol, with cached input at $0.10. GPT-6 Sol (gpt-6-sol, 2026-09-22) and Luna (gpt-6-luna) are the earlier cost tiers. ChatGPT Plus gets Astra in Work and Codex; Chat “GPT-6 Pro” is Pro/Business/Enterprise. GPT-6.1 Sol, Sol, and Luna are in the API and in Work and Codex for paid plans. From 2026-10-07, GPT-6 with Intelligent UI (interactive charts, forms, buttons, and small tools inside answers) powers the ChatGPT Chat tab: GPT-6 Sol for Plus, Pro, Business, and Enterprise, and GPT-6 Luna for Free and Go from 2026-10-08. GPT-5.6 remains available. The GPT-6.1 Sol model page does not say gpt-6-sol was removed.
Vision · Tool calling · Thinking · MCP · Coding
Last reviewed: 8 October 2026
Overview
Capabilities
- Vision: Yes
- Audio input: No
- Tool calling: Yes
- Thinking: Yes
- MCP: Yes
- Coding: Yes
- Structured output: Yes
Technical specifications
- Provider
- OpenAI
- License
- Proprietary
- Context window
- 1.1M
- Parameters
- Undisclosed
- Architecture
- Transformer (proprietary)
- Release
- 2026-09
- Modalities
- Text, Image
- Vision
- Yes
- Audio input
- No
- Tool calling
- Yes
- Thinking
- Yes
- MCP
- Yes
- Open weights
- No
- API
- Yes
- Pricing (input)
- ~$10 per 1M tokens (Standard, ≤272K input)
- Pricing (output)
- ~$50 per 1M tokens (Standard, ≤272K input)
Supported modalities
Text · Image
Context window
1.1M (1,050,000 tokens)
Pricing
Astra Standard: $10 input / $1 cached input / $12.50 cache writes / $50 output per 1M tokens. GPT-6.1 Sol (2026-09-29): $2 / $0.10 cached input / $2.50 cache writes / $10 output. GPT-6 Sol (2026-09-22): $2 / $0.20 / $2.50 / $10. GPT-6 Luna: $0.10 / $0.01 / $0.125 / $0.50. Prompts over 272K input tokens are 2× input and cache and 1.5× output for the full request. API model pages price Fast mode at 2× Standard; Batch and Flex are 50% of Standard. Astra Ultrafast is a service tier; the guide does not print a dollar rate. Verify openai.com/api/pricing/.
Availability
API gpt-6-astra plus AWS/Bedrock and Microsoft Foundry (Standard and Provisioned Throughput; Global and US Data Zone). ChatGPT surfaces differ: Plus includes Astra in Work and Codex, not the Chat model picker (Plus Chat uses GPT-6 Sol with Intelligent UI from 2026-10-07); in Chat, Astra powers GPT-6 Pro for Pro, Business, and Enterprise (Enterprise off by default). Usage is included in existing ChatGPT allowances with optional extra credits. Pro/Business/Enterprise also get GPT-6 Astra Pro. Zero Data Retention for eligible API customers. Generally available in GitHub Copilot (Pro+/Max/Business/Enterprise, 2026-09-04). Snowflake Cortex AI private preview as of 2026-09-09 (CoCo, CoWork, Cortex Agents, AI Functions, Cortex Inference). Agents API public beta (2026-09-10) uses gpt-6-astra in hosted or self-hosted sandboxes; Agents API is not ZDR-eligible. ChatGPT for Financial Services (2026-09-10) is an eligible-institutions Work SKU that pairs Astra with licensed market data — not a general ChatGPT plan. Voice is a separate API model (gpt-live-1, GA 2026-09-10); Astra remains text/image. Not supplied to Cursor under OpenAI’s proposed Cursor contract wind-down (shutoff 2026-11-12). Public Astra refuses advanced offensive-cyber tasks; Daybreak access is the gated cyber track. Codex can keep searchable notes across context windows (experimental in config.toml; planned default for Astra). Async tool calling and mid-turn steering are Astra-only API features. GPT-6 Sol and Luna (2026-09-22) are API ids gpt-6-sol and gpt-6-luna (1,050,000 context, 128,000 max output; Sol knowledge cutoff 2026-04-20, Luna 2026-05-18). Both are in ChatGPT Work and Codex for Plus, Pro, Business, Enterprise, and Edu. Since 2026-10-07 they also power GPT-6 with Intelligent UI in the Chat tab (Sol for paid tiers; Luna for Free and Go from 2026-10-08; Enterprise availability depends on admin settings). Work and Codex models did not change in that rollout. GPT-6.1 Sol (gpt-6.1-sol, 2026-09-29) is in the API and in Work and Codex for those same paid plans. It has a 1,050,000-token context, 128,000 max output, and a 2026-04-30 knowledge cutoff. Tool calling uses the Responses API; Chat Completions is supported without tool calling. Astra Ultrafast sets service_tier to ultrafast on gpt-6-astra and is available to all API users at low default TPM (500K for tiers 1–3, 1M for tier 4, 5M for tier 5), US and global processing only. GPT-6.1 Sol Ultrafast is announced for the coming days and is not in that guide.
Use cases
- Computer-use and browser agents
- Long-horizon software engineering and Codex
- Professional documents, slides, and CAD-adjacent workflows
- Scientific analysis with terminal/code tools
Strengths
- OpenAI’s current peak flagship above GPT-5.6
- Computer-use and coding-agent focus in the launch report
- API id is stable (gpt-6-astra) with Standard, Fast, and Ultrafast service tiers
- GPT-6.1 Sol (gpt-6.1-sol) is the current $2/$10 Sol id, with cached input at $0.10
- 1,050,000-token context; 128,000 max output tokens (official API docs)
Limitations
- Closed weights; Plus ChatGPT Chat picker does not include Astra (Work/Codex only)
- Standard API list price is above GPT-5.6 Sol promo rates
- Not available as a Cursor backend; Enterprise Chat access is off by default
Related guides
Related benchmarks
Related research
- GPT-6 Astra: A new generation of intelligence
Original Paper
- GPT-6 Astra model (OpenAI API)
Evaluation
- Introducing GPT-6.1 Sol
Original Paper
- GPT-6.1 Sol model (OpenAI API)
Evaluation
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