The value pick of the GPT-5.6 family — performance competitive with GPT-5.5 at a fraction of the price. Built for the majority of everyday production work.
Terra lands at $2 / 1M input and $12 / 1M output — cut from $2.50/$15 on July 30, 2026 — and remains roughly 2.5× cheaper than Sol for competitive everyday quality.
Terra is the middle child of the GPT-5.6 family — the model OpenAI expects most developers to reach for day to day. Released publicly on July 9, 2026 alongside Sol and Luna at the $2.50 / $15 per-1M rate of the GPT-5.4 model it replaced, OpenAI cut its price further to $2 / $12 per 1M tokens on July 30, 2026, while matching much of GPT-5.5's quality at a fraction of the cost.
Terra doesn't ship the max/ultra reasoning modes that make Sol distinctive; instead it targets the sweet spot of price and capability for high-volume production work. For teams migrating off GPT-5.5, it's the natural default — similar output quality, meaningfully lower spend.
Terra is a strong generalist: writing, code, vision, structured extraction, and reliable tool use across multi-turn loops. It gives up the deepest reasoning on the hardest problems (where Sol's Ultra mode earns its cost) but handles the vast majority of everyday tasks without the flagship price tag. The large context window keeps it viable for document Q&A and repo-scale coding.
| Model | Input / 1M | Output / 1M | Context |
|---|---|---|---|
| GPT-5.6 Terra | $2 | $12 | 1M |
| GPT-5.6 Sol | $5 | $30 | 1M |
| GPT-5.6 Luna | $0.20 | $1.20 | 1M |
| Claude Sonnet 5 | $2 | $10 | 1M |
| Gemini 3.1 Pro | $2 | $12 | 1M |
Terra's closest rivals are Claude Sonnet 5 (equal on input, higher on output since Sonnet 5's price became permanent at $2/$10) and Gemini 3.1 Pro (cheaper, with a per-request tier surcharge above 200K tokens). Against its own family, it's the value option below Sol and above Luna.