Tencent open-sources Hunyuan Hy4-preview: 770B params, 1M context, ~#3 among open models

机器之心 · wechat · 2026-08-28

Tencent Hunyuan released and open-sourced Hy4-preview: 770B total parameters (MoE, 49B active), 1M context window, weights and FP8 version under Apache 2.0. A big step from Hy3-preview (295B/21B/256K). API pricing: ¥6/M input tokens, ¥18/M output, ¥0.3/M cached input.

Benchmarks: Terminal-Bench 2.1 up from 70.8 to 85.4, DeepSWE 28.0 to 64.3, GPQA Diamond 92.3; it scores 1633 on CodeArena:WebDev (AutoEval), roughly #5 overall and #3 among open models. Positioned "for productivity," it targets long-horizon software engineering, multi-file office analysis, Unity/Unreal game prototyping from a single prompt, and scientific research; 163 internal experts blind-rated 203 engineering tasks at 2.99/4, slightly above GLM5.3 (2.92) and Kimi K3 (2.94).

Notably, the model participated in Hunyuan's own training pipeline, data strategy, and kernel optimization, lifting end-to-end inference throughput 31.8% over baseline.

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