GPT-5.6 Terra
GPT-5.6 Terra
The sensible middle of the summer line-up, now squeezed out by GPT-6.1 Sol.
Updated
The read
Terra was the balanced member of the GPT-5.6 family: quick enough for product work, strong enough for most reasoning, and supported by every framework. GPT-6 has no Terra, and GPT-6.1 Sol now costs the same for input and less for output while scoring far higher, which leaves Terra little reason to exist for new work. It remains active on the API, and its price was cut by a fifth at the end of July.
Where it shines
- Every framework ships an adapter for it
- Million-token context at a mid-tier price
- Predictable structured output in production
Worth knowing first
- GPT-6.1 Sol scores far higher for the same input price
- No GPT-6 successor, so the line ends here
Index score
83.6
Provisional. This score is read from the product's public capability, not from the one-prompt rebuild the fully reviewed entries went through, so treat it as a placing rather than a verdict.
- Rank
- 27 of 73
- Builds
- LLMs
- Category
- Frontier
- Output
- Text, code and tool calls over an API
- Pricing
- Paid only
- Best for
- Existing product work already tuned against it
Scores are our own editorial judgement, weighted craft 55, speed 10, control 15 and value 20.
Compare it with
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- 03Gemini 4 ArgonGemini 4 ArgonProvisionalTop of the human-preference leaderboard, and almost nobody can use it yet.Frontier modelPaid only90.6
- 04GPT-6.1 SolGPT-6.1 SolProvisionalNear-Astra answers at a fifth of the price. The OpenAI model most teams should deploy now.Frontier modelPaid only90.3
