GPT-5.6 Sol Pricing & Specs
GPT-5.6 Sol: OpenAI's Latest Frontier Model
OpenAI previewed the GPT-5.6 model family on June 26, 2026, featuring three tiers: Sol (flagship), Terra (mid-range), and Luna (efficient).
Pricing
| Model | Input | Output | Context |
|---|---|---|---|
| GPT-5.6 Sol | $5.00 / 1M tokens | $30.00 / 1M tokens | 128K |
| GPT-5.6 Terra | $2.50 / 1M tokens | $15.00 / 1M tokens | 128K |
| GPT-5.6 Luna | $1.00 / 1M tokens | $6.00 / 1M tokens | 128K |
Key Features
- Ultra mode — Spawns multiple sub-agents for parallel reasoning, boosting TerminalBench-2.1 score from 88.8% to 91.9%
- Extended thinking — Model can dynamically adjust how much compute to spend on a task
- Government-limited access — Currently only available to trusted partners per U.S. government request
- Rivals Claude Mythos 5 — Positioned as direct competitor to Anthropic's flagship
Benchmark Performance
GPT-5.6 Sol achieves 88.8% on TerminalBench-2.1 (89 complex programming tasks), increasing to 91.9% with ultra mode enabled.
Access Status
GPT-5.6 is currently in limited preview. OpenAI has restricted rollout to trusted partners following a request from the Trump administration citing national security concerns. Full public availability timeline is unconfirmed.