openai
OpenAI: GPT-5.6 Terra Pro API Pricing
OpenAI: GPT-5.6 Terra Pro costs $2.00 per 1M input tokens and $12.00 per 1M output tokens (cache reads: $0.200). Context window: 1.1M. Prices verified 2026-08-23 · source
Input / 1M tokens
$2.00
Output / 1M tokens
$12.00
Context window
1.1M
Max output
128K
What would OpenAI: GPT-5.6 Terra Pro cost you per month?
| Workload | Requests/mo | Avg tokens (in/out) | Est. monthly cost |
|---|---|---|---|
| Light chatbot | 10,000 | 800 / 400 | $64.00 |
| Coding agent | 5,000 | 8,000 / 2,000 | $200.00 |
| RAG pipeline | 30,000 | 4,000 / 500 | $420.00 |
| Doc summarizer | 2,000 | 20,000 / 1,000 | $104.00 |
Estimates use list prices without prompt caching. Caching can cut input cost by up to 90% on repeated context.
About OpenAI: GPT-5.6 Terra Pro
GPT-5.6 Terra Pro is the same underlying model as [GPT-5.6 Terra](https://openrouter.ai/openai/gpt-5.6-terra), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. Learn more in OpenAI's docs: https://developers.openai.com/api/docs/guides/reasoning#reasoning-mode