GPT-5.6 Terra vs Hy4 preview
GPT-5.6 Terra and Hy4 preview are closely matched at 51.2 and 51.1 on the LLM Stats Score.
OpenAI · Tencent · Updated for 2026
Which is better?
GPT-5.6 Terra and Hy4 preview are closely matched on the overall LLM Stats Score at 51.2 and 51.1.
In the 7 individual benchmarks reported for both models, GPT-5.6 Terra wins 4; this is a narrower head-to-head signal than the composite indexes.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose GPT-5.6 Terra
- you value its reported benchmark strengths — it wins 4 of 7 exact shared results
Choose Hy4 preview
- you want the most recent training data — it shipped Aug 2026
- you need open weights you can self-host or fine-tune
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
45 reported for GPT-5.6 Terra · 32 for Hy4 preview
GPT-5.6 Terra outperforms in 4 benchmarks (Agents' Last Exam, DeepSWE, GPQA, Terminal-Bench 2.1), while Hy4 preview is better at 3 benchmarks (AutomationBench, SWE-Bench Pro, Toolathlon).
GPT-5.6 Terra has a slight edge in benchmark performance.
Human preference
Blind head-to-head votes and playground preference scores
Context Window
Maximum input and output token capacity
Only GPT-5.6 Terra specifies input context (1,050,000 tokens). Only GPT-5.6 Terra specifies output context (128,000 tokens).
Input capabilities
Documented input modalities across available providers
GPT-5.6 Terra supports multimodal inputs, whereas Hy4 preview does not.
GPT-5.6 Terra can handle both text and other forms of data like images, making it suitable for multimodal applications.
GPT-5.6 Terra
Hy4 preview
License
Usage and distribution terms
GPT-5.6 Terra is licensed under a proprietary license, while Hy4 preview uses Apache 2.0.
License differences may affect how you can use these models in commercial or open-source projects.
Proprietary
Closed source
Apache 2.0
Open weights
Release Timeline
When each model was launched
GPT-5.6 Terra was released on 2026-07-09, while Hy4 preview was released on 2026-08-28.
Hy4 preview is 2 months newer than GPT-5.6 Terra.
Jul 9, 2026
1 months ago
Aug 28, 2026
1 weeks ago
1mo newerKnowledge Cutoff
When training data ends
GPT-5.6 Terra has a documented knowledge cutoff of 2026-02-16, while Hy4 preview's cutoff date is not specified.
We can confirm GPT-5.6 Terra's training data extends to 2026-02-16, but cannot make a direct comparison without Hy4 preview's cutoff date.
Feb 2026
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Outputs Comparison
Judge for yourself.
Run your own prompts against GPT-5.6 Terra and Hy4 preview side-by-side, then vote on the output you prefer.
FAQ
Common questions about GPT-5.6 Terra vs Hy4 preview.