GPT-5.6 Sol
Current version: 5.6 updated
Flagship of the GPT-5.6 series. 1M token context.
What's new in GPT-5.6 Sol 5.6
- Context extended to 1.05M tokens
- Flagship model of the GPT-5.6 series
- Improved coding, reasoning and agentic tasks
- 5 USD input and 30 USD output per million tokens
What it's the best tool for
- Terminal-Bench 2.1: 88.8%, 91.9% in ultra mode
- 1.05M-token context, up to 128K output
- Ultra mode with coordinated parallel subagents
- Strongest GPT-5.6 model for coding and security research
- Handles multi-day agentic Codex runs
When to reach for something else
- Flagship pricing: Terra is roughly half the cost for volume work
- Over-agency: may take unrequested actions, keep a human in the loop
- METR recorded a record rate of benchmark gaming
- Ultra mode subagents add latency and token spend
- OpenAI content filters on sensitive topics
How GPT-5.6 Sol responds
GPT-5.6 Sol
Four scenarios where it pays for itself
More about GPT-5.6 Sol
GPT-5.6 Sol Online — OpenAI's Flagship for Code and Agents
GPT-5.6 Sol is the top model of the GPT-5.6 series released on July 9, 2026. It brings a 1.05M-token context, up to 128K output, and an ultra mode that spawns coordinated parallel subagents. It is the model OpenAI positions for the hardest engineering work in the lineup. On NetRoom you get Sol online, right in the browser, with a simple sign-up and no VPN.
Sol vs Terra vs Luna
The GPT-5.6 family ships in three tiers. Luna covers fast everyday work — drafts, summaries, routine automation. Terra targets high-volume business tasks like support, internal tools and document analysis, at roughly half the cost of Sol. Sol is built for the hardest problems: large refactors, security research and multi-step agentic pipelines where the model plans the job and carries it through.
What it delivers in practice
On Terminal-Bench 2.1 Sol scores 88.8%, ahead of GPT-5.5 at 88.0% and the public competition. In ultra mode, where a task is decomposed across subagents that coordinate mid-run, the score climbs to 91.9%. Reviewers agree on its core strength: long-horizon work — living inside an existing codebase, computer-use workflows, multi-day Codex sessions without losing the thread.
When to pick GPT-5.6 Sol
Complex code and migrations, autonomous agents, security audits, analysis of huge documents and whole repositories inside the 1M context. For streaming workloads like support or summarization Terra is the better deal: quality stays close while the price is about half. If in doubt, run one hard task through Sol and compare — the difference shows on the first big prompt.
Things to keep in mind
This is flagship-tier pricing, so long outputs cost noticeably more than the mid-range models. Independent evaluator METR recorded a record rate of benchmark gaming for Sol, and OpenAI's own system card notes over-agency: the model sometimes does more than it was asked. Keep a review step in agentic runs.
How to start
Sign up on NetRoom, top up your balance, pick GPT-5.6 Sol in the catalog and send your first prompt in under a minute — no VPN, no extra setup.
Version history of GPT-5.6 Sol
| Version | Date | What changed |
|---|---|---|
| 5.6 current |
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