Qwen3.5-397B-A17B vs Seed-1.8

Alibaba / Qwen

Qwen3.5-397B-A17B is a 397-billion-parameter mixture-of-experts model from Alibaba's Qwen team, released in February 2026 as the open-weight flagship of the Qwen3.5 series, featuring 17 billion active parameters per forward pass through a hybrid linear-attention and sparse-MoE architecture based on Gated Delta Networks. The model was co-trained on text, images, and video using early fusion, making it natively multimodal across a 262K token context window, while achieving significantly higher inference throughput than comparable dense models due to its sparse computation design. At release it was one of the most capable open-weight models publicly available, offered under Apache 2.0 and accessible through Alibaba's DashScope API as the Qwen3.5-Plus endpoint.

ByteDance

Seed-1.8, developed by ByteDance Seed, is a generalized agentic large language model supporting text and image input, with industry-leading GUI agent capabilities and improvements in multimodal reasoning over its predecessor Seed1.5-VL. It targets information retrieval, code generation, GUI interaction, and complex agentic workflows requiring robust multimodal understanding.