OpenAI · released Jul 9, 2026
GPT-5.6 Terra
GPT-5.6 Terra is OpenAI's older mid-tier model, and GPT-6.1 Terra now costs half as much.
4 months oldThinks before answering
- Input price
- $2 / M
- Output price
- $12 / M
- Context
- 1.1M tokens
- Longest reply
- 128K
- Reads
- text, image, pdf
- Knows up to
- 2026-02-16
Where it shines
- It scores 1472 in the document arena.
- It scores 93.3 on GPQA.
Where it struggles
- It ranks 27th on the agent leaderboard.
- Its SimpleQA score of 43.2 is low.
Where you can use it
- OpenAI APIAPI$2 in / $12 out per million tokens.
- OpenRouterAPIListed as
openai/gpt-5.6-terra
How it scores on each job
Scores run 0 to 100 and blend every measure we have for that job. The number after the dot is its rank among the 33 models in the lineup.
The evidence
| Measure | Score | Rank in lineup | Source |
|---|---|---|---|
| Epoch Capabilities Index | 160 | #8 | Epoch AI |
| LMArena text | 1448 | #19 | LMArena |
| LMArena hard prompts | 1469 | #18 | LMArena |
| LMArena instruction following | 1455 | #20 | LMArena |
| LMArena multi-turn | 1453 | #19 | LMArena |
| LMArena creative writing | 1413 | #23 | LMArena |
| LMArena writing & language | 1432 | #21 | LMArena |
| LMArena coding | 1486 | #18 | LMArena |
| LMArena math | 1466 | #22 | LMArena |
| LMArena business & finance | 1448 | #19 | LMArena |
| LMArena legal & government | 1462 | #19 | LMArena |
| LMArena medicine | 1432 | #21 | LMArena |
| Vision Arena | 1271 | #16 | LMArena |
| Document Arena | 1472 | #3 | LMArena |
| Agent Arena | #27 | #17 | LMArena |
| GPQA Diamond | 93% | #11 | Epoch AI |
| FrontierMath | 86% | #8 | Epoch AI |
| SimpleQA Verified | 43% | #18 | Epoch AI |
| ARC-AGI-2 | 84% | #10 | Epoch AI |
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