On April 29, 2026, Tencent Hunyuan made its offline translation model for mobile devices, named Hy-MT1.5-1.8B-1.25bit, available as open-source. This innovative model condenses a substantial translation framework—capable of supporting 33 languages and facilitating 1,056 translation directions—into a mere 440MB. This compact size allows the model to operate seamlessly on mobile devices without the need for an internet connection, and notably, its translation quality outperforms that of Google Translate.

Constructed on the foundation of the Hy-MT1.5 model, it delivers translation performance on par with commercial translation APIs and large-scale models boasting 235 billion parameters, all while utilizing only 1.8 billion parameters. To accommodate the diverse needs of mobile users, Tencent has introduced two quantization compression options: a 2-bit and a 1.25-bit variant. The 2-bit model, with a size of 574MB, is ideally suited for mid-range to high-end mobile devices. Meanwhile, the 1.25-bit model, at a mere 440MB, ensures compatibility across all mobile device types.

Tencent has made all model weights, code, and technical reports publicly accessible. Additionally, a demo version tailored for the 'background word-picking mode' has been released, further enhancing the model's practicality and user experience.