GPT-5.6 Terra
ECI#7
159GPT-5.6 Terra is a closed-weights model from OpenAI, released July 9, 2026. It has an ECI score of 159 and ranks 7th of 249 tracked models. At the time of its release, it ranked 4th of 230 tracked models. At $2/Mtok for input tokens and $12/Mtok for output tokens, it is less expensive per token than similarly-capable models.
Input price$2 / 1M tokens
Output price$12 / 1M tokens
ParametersUnknown
Training computeUnknown
GPT-5.6 Terra vs select alternatives
Reasoning
| Domain | Benchmark | GPT-5.6 Terra | |||
|---|---|---|---|---|---|
ECI scoreBest score 166 | 159 | 162 | 163 | 155 | |
| Ranking | #7 | #5 | #3 | #27 | |
| Conceptual reasoning | ARC-AGI-2Best score 95.0% | ||||
ARC-AGI-1Best score 98.5% | |||||
| Games | Chess PuzzlesBest score 72.0% | ||||
Mystery Game PuzzlesBest score 84.0% | |||||
| Mathematics | FrontierMath Tiers 1-3 (v2)Best score 93.7% | ||||
FrontierMath Tier 4 (v2)Best score 97.6% | |||||
OTIS Mock AIME 2024-2025Best score 100.0% | |||||
| Science | GPQA DiamondBest score 95.8% | ||||
| World knowledge | SimpleQA VerifiedBest score 75.6% |
