Doubao

Doubao (Chinese 豆包, “little bean”) is a family of large language models developed by ByteDance that powers the Doubao AI assistant — the most popular AI chatbot in China. The assistant launched in August 2023 and reached about 60 million monthly active users by November 2024, growing to 330 million users by May 2026 (when paid subscription tiers were also introduced).

Doubao models are built on a mixture-of-experts (MoE) architecture with an integrated training-inference design. According to ByteDance, the Doubao-1.5-pro model — with activated parameters equal to about 1/7 of a dense model — surpassed that dense model’s quality; pretraining spanned roughly 9 trillion tokens.

The family is multimodal: it supports text, image understanding (with native dynamic resolution) and speech via an end-to-end Speech2Speech framework. The models also offer a “deep thinking” (reasoning) mode — the Doubao-1.5-pro-AS1-Preview variant surpassed reasoning models such as o1-preview on the AIME benchmark.

The latest generation is Doubao Seed 2.0 (stable release on 14 February 2026). The models are available through the Volcano Engine (Volcengine) platform and ByteDance apps on iOS, Android and the web; the international variant of the assistant is Cici/Dola. These are proprietary models.