Doubao 1.5 Pro

Doubao 1.5 Pro is ByteDance’s flagship foundation model, launched on January 22, 2025 through its Volcano Engine cloud platform and the Doubao consumer assistant app. It uses a sparse mixture-of-experts architecture that ByteDance says delivers performance comparable to a dense model roughly seven times its active parameter count, and it ships in both a 32K and a 256K context-window variant. ByteDance reported that it matched or beat GPT-4o and Claude 3.5 Sonnet on a range of benchmarks, including math and reasoning tests, while pricing its API at a fraction of what those competitors charged.

The aggressive pricing was as much the story as the benchmarks: ByteDance framed Doubao 1.5 Pro as roughly 50 times cheaper than comparable models from Western labs on a per-token basis, part of a broader price war among Chinese AI labs through 2025. It’s proprietary and closed-weight, accessible only through ByteDance’s API and apps, and it has since been followed by newer Doubao and Seed-branded tiers with reasoning and multimodal upgrades.