Doubao Seed 2.1 Pro

Overview

Doubao Seed 2.1 Pro is ByteDance's next-generation flagship LLM, announced June 23-24, 2026 at the annual Volcano Engine conference. Positioned as a "deep thinking" agent-oriented model, it targets three areas: end-to-end delivery of complex coding projects, long-horizon agentic task execution (planning, continuous self-repair), and multimodal understanding. ByteDance internally claims "Claude Opus 4.6-4.7 class" performance — but no independent benchmarks have been published yet, which is why our benchmark columns remain empty for this model. What can be stated with certainty is the price positioning: roughly $0.83/M input tokens and $4.14/M output via the Volcano Engine API (¥6/¥30), a fraction of Western flagship pricing, with a 256K-token context window. Its predecessor Seed 2.0 Pro already proved ByteDance can hit frontier benchmarks (98.3 on AIME 2025, 76.5 on SWE-bench Verified) at rock-bottom prices. Caveats for professional European use: inference is hosted in mainland China or Singapore/Hong Kong (a deal-breaker if your compliance requires EU/US data residency), tight rate limits on direct access (~5 RPS to start), and Chinese-first optimization — long-context English degraded past ~150K tokens on the previous generation. A cheaper, low-latency Turbo variant targets high-volume deployments.

Skill profile

Who is it for

Ideal use cases

• Long-horizon agentic workflows (planning, self-repair)
• Complex software engineering on a tight budget
• Large-scale multimodal understanding

Access & availability

Key specifications

Privacy