LLM Releases

Model family timeline

Last updated Jun 23, 2026

Seed model releases

A source-backed timeline for the Seed model family, collecting release dates, labs, access details, context windows, and major lifecycle changes.

2
Models
1
Labs
0
Open
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Recent

2 models

Seed 2.1 Turbo

Available
ByteDance SeedProprietary

The low-cost, low-latency tier of ByteDance's Seed 2.1 family (served as Doubao-Seed-2.1-turbo), built for large-scale production with full features and performance ByteDance positions as comparable to Seed 2.1 Pro. Shares the family's coding, long-chain agent, and multimodal-understanding focus and 256K-token context, priced for high-volume online calls. Proprietary; available via Doubao and Volcano Engine. List price ¥3 / ¥15 per million input/output tokens — roughly half the Pro tier.

Undisc.256K ctxJun 23, 2026

Seed 2.1 Pro

Available
ByteDance SeedFrontierProprietary

ByteDance's flagship next-generation agent model (served as Doubao-Seed-2.1-pro), built for the "coding and agent era." A deep-thinking model tuned for strong demand understanding, long-horizon planning, and continuous self-repair across complex coding, long-chain agents, and multi-step engineering delivery, with a 256K-token context. ByteDance reports its core coding, agent, and multimodal capabilities are comparable to GPT-5.5, with the highest score on GDPVal, top-tier results on the Agents' Last Exam, the highest score on MobileWorld, and SOTA results across several visual and video-understanding benchmarks (CharXiv-RQ, MeasureBench, TVBench, TOMATO). Proprietary; available via Doubao and Volcano Engine. List price ¥6 / ¥30 per million input/output tokens.

Undisc.256K ctxJun 23, 2026