OpenAI has significantly broadened access to its cutting-edge artificial intelligence capabilities by introducing two new, lower-cost models: GPT-6 Sol and GPT-6 Luna. These additions to the GPT-6 family aim to make advanced AI more accessible and affordable for a wider range of users, including professionals, developers, and businesses seeking robust performance without incurring higher computing expenses.
GPT-6 Sol and Luna: Bridging Performance and Cost
Positioned strategically below the flagship GPT-6 Astra, Sol and Luna bring many of Astra's powerful features to more budget-friendly tiers. OpenAI emphasizes that these models are engineered for demanding professional workflows, intricate coding tasks, and high-volume, repeatable operations, highlighting substantial improvements in overall efficiency.
The company attributes reduced serving costs to advancements in caching and inference technologies. This efficiency gain has allowed OpenAI to slash API prices for both Sol and Luna by 50% compared to the promotional rates of their GPT-5.6 predecessors.
GPT-6 Sol: Power for Complex Tasks
GPT-6 Sol is specifically tailored for more complex professional work, advanced coding, and sophisticated agentic workflows. It is designed to handle intricate tasks while offering higher usage limits at a significantly reduced cost. In performance benchmarks:
- AutomationBench: GPT-6 Sol, operating at high effort, outperformed Claude Opus 5 at maximum effort, achieving this at just 9% of Claude's per-task cost.
- Coding (FrontierCode): Sol demonstrated substantial improvements over GPT-5.6 Sol and matched the performance of Claude Fable 5.1 xhigh, but at a much lower operational expense.
- Computer Use (OSWorld 2.0 offline): Sol scored 60.5% at xhigh effort, closely matching Claude Opus 5's 60.3% at medium effort, while costing approximately 80% less per task.
GPT-6 Luna: Efficiency for High-Volume Operations
GPT-6 Luna focuses on delivering efficient, repeatable, and high-volume task execution. It builds upon its predecessor, showing notable gains:
- AutomationBench: Luna improved upon GPT-5.6 Luna by 5.4 percentage points at high effort, costing 58% less per task.
More Accessible Pricing and Availability
The new API pricing structure makes these advanced models more accessible:
- GPT-6 Sol: Costs $2 per 1 million input tokens and $10 per 1 million output tokens.
- GPT-6 Luna: Costs $0.10 per 1 million input tokens and $0.50 per 1 million output tokens.
Both models are available immediately through the OpenAI API. Furthermore, GPT-6 Sol and Luna are integrated into ChatGPT Work and Codex for Plus, Pro, Business, Enterprise, and Edu subscribers. Free and Go users can access GPT-6 Luna via the desktop application.