Positioned between Sol and Luna, GPT-5.6 Terra is the balanced tier of the GPT-5.6 generation OpenAI launched on July 9, 2026. It lands within a few points of the Sol flagship on most published evaluations, delivering roughly the capability of the prior GPT-5.5 flagship as the family's everyday default, and it shares the generation's 1.05 million token context window and 128K output ceiling. Terra is the sensible pick for the bulk of production workloads, from coding assistants to document analysis to routine agent pipelines. Its long-context recall stays close to the flagship's, so multi-document synthesis and large-repository reasoning hold up well, and reasoning, vision, tool use, and structured output come standard.
GPT-5.6 Terra runs on 2 different routes through the Opper gateway. Compare residency, ZDR, and training posture at a glance β full data-handling detail per route below.
| Provider | Region | Zero data retention | Training | Input | Output |
|---|---|---|---|---|---|
| Multi | Zero data retention | No | $2.00 | $12.00 | |
| US | Enterprise | No | $2.00 | $12.00 |
GPT-5.6 Terra runs on 2 independently monitored routes through the Opper gateway. A direct integration leaves you on one of them, the gateway serves whichever is healthy.
Measured over the last 30 days from each provider's official status feed via StatusGator. Refreshed hourly. See uptime for every provider Opper monitors.
Each route hosting GPT-5.6 Terra has its own privacy posture, residency, and GDPR terms. Postures are maintained by Opper with a last-verification timestamp.
Zero data retention is on by default on Pay-as-you-go β no action required. No training on customer data. GLOBAL; SCCs; DPA available.
Zero data retention is available via Opper Enterprise contract. No training on customer data. US; SCCs; DPA available.
Independent benchmark scores β composite indices for reasoning, coding, and math, plus individual eval scores where available.
Call GPT-5.6 Terra through the Opper gateway with one API key. Let your coding agent set it up, or call it directly β Opper is drop-in compatible with the OpenAI, Anthropic, and Google AI SDKs.
Copy this and paste it into a coding agent like Claude Code, Cursor or Codex and it'll wire up Opper for you.
import OpenAI from "openai";const client = new OpenAI({apiKey: process.env.OPPER_API_KEY,baseURL: "https://api.opper.ai/v3/compat",});const completion = await client.chat.completions.create({model: "openai/gpt-5.6-terra",messages: [{ role: "user", content: "Hello" }],});console.log(completion.choices[0].message.content);
Side-by-side on privacy, EU hosting, pricing, and benchmarks.
