GPT-5.6 Terra

• 🆕 Mid-tier of OpenAI's GPT-5.6 family, between Sol and Luna.
• 🎯 Balanced for everyday coding, reasoning, and agentic tasks.
• 📏 One-million-token context window.
• 👁️ Multimodal vision input supported.
• 🔧 Function calling, web search, and reasoning built in.
• 🏢 Released July 2026 alongside the Sol, Terra Pro, and Luna tiers.
• 📚 Higher-capacity Terra Pro variant available alongside it.

OpenAI

OpenAI is an American artificial intelligence research organization headquartered in San Francisco, structured as both a for-profit public benefit corporation and a nonprofit foundation. The lab developed the GPT family of large language models, the DALL-E…

GPT-5.6 Terra is the balanced middle tier of OpenAI's GPT-5.6 generation, sitting between the flagship GPT-5.6 Sol and the cost-efficient GPT-5.6 Luna, with a higher-capacity GPT-5.6 Terra Pro variant alongside it. It carries a one-million-token context window plus vision, function-calling, and web-search capabilities, and is aimed at everyday coding, reasoning, and agentic work.

Terra is the mid-tier successor to OpenAI's earlier general-purpose releases such as GPT-5.5 and GPT-5.4. With GPT-5.6, OpenAI groups the generation into three named tiers — Sol, Terra, and Luna — so that a durable capability tier can advance across generations rather than relying on "mini" or "instant" labels. Terra occupies the balance point, trading some flagship capability for lower cost and latency.

The model exposes adjustable reasoning effort and supports OpenAI's function-calling and web-search tooling, making it suited to multimodal assistants and agentic pipelines that mix text and image input. It was released on July 9, 2026 as part of the broader GPT-5.6 lineup, which also includes the Terra Pro, Sol, Sol Pro, Luna, and Luna Pro tiers. ---