Lower-cost Seed 2.1 tier with text, image and video input, reasoning mode and 262K context for agent and coding pipelines.
Modality:
Text
Image
PDF
model ID
bytedance-seed/seed-2-1-turbo
Output Speed *
N/A
tok/s
Intelligence Index *
N/A
/ 100
Context Window *
262144
tokens
Input price
3
Anytoken
Output price
15
Anytoken
Seed 2.1 Turbo: Multimodal Agent and Coding Capacity at the Lower-Cost Seed Tier
Seed 2.1 Turbo is ByteDance Seed's faster, lower-cost tier of the Seed 2.1 family. It was introduced alongside Seed 2.1 Pro at Volcano Engine's FORCE conference in June 2026. It accepts text, image and video input, returns text, and offers a reasoning mode with tool calling inside a 262K-token context window. ByteDance positions it for coding and long-horizon agent workflows where call volume matters more than peak capability. That makes it a candidate default for agent pipelines and multimodal document processing.
Test Seed 2.1 Turbo on your agent workload through AnyAPI.ai.
Performance
Pro-Class Feature Set at the Volume Tier, Without Separate Benchmarks
Seed 2.1 Turbo's strength is breadth at the lower-cost tier. It carries the Seed 2.1 feature set of project-cycle coding, multi-step tool use, and text, image and video understanding, inside a 262,144-token window. ByteDance has not published Turbo-specific benchmark scores, and its claim that the Seed 2.1 series matches GPT-5.5 is vendor-reported and unverified. Treat Turbo as a volume-oriented default, validate quality on your own tasks, and keep Pro available as the escalation path for the hardest cases.
Technical Specifications
What the model supports
Seed 2.1 Turbo accepts text, image and video input and returns text only. The context window is 262,144 tokens. Volcano Engine lists maximum output at 262,144 tokens with a 4K default, so long generations require raising the response limit explicitly. It also lists a separate 256K chain-of-thought limit, so budget response and reasoning tokens deliberately. Some third-party hosts cap output lower, so verify limits on the route you use.
Verified Specifications —
Seed 2.1 Turbo
*
Input modalities
Text
Image
PDF
output modalities
Text
Context window
262144
tokens
Maximum output tokens
262144
Reasoning
Yes
Knowledge cutoff
June 2026
Pricing (standard)
3
AnyTokens in
/
15
AnyTokens out
Limitations & Trade-offs
1
No Turbo-specific benchmarks. ByteDance has not published scores for Turbo separate from Pro, and its claim that Seed 2.1 matches GPT-5.5 is vendor-reported. Teams cannot infer Turbo's coding or agent accuracy from public data. Run your own evaluation on representative tasks before replacing a model whose results you already know, and use Seed 2.1 Pro or another proven model where error tolerance is low.
2
Text-only output. Seed 2.1 Turbo accepts text, image and video but returns text only, so it cannot generate images, audio or video. Audio input is not listed for this model. Pipelines that need speech input, image generation or audio output must pair it with a separate specialist model. Its 262K context is also smaller than the roughly 1M windows offered by some competing models, which matters for whole-repository or very large corpus prompts.
3
Reasoning overhead and modest measured speed. Deep thinking is available, and one host's listing shows thinking enabled by default at high effort, which adds tokens and latency to simple requests. OpenRouter's listing showed about 36 tokens per second at P50, a modest figure for a model positioned as faster. For real-time chat or simple classification, lower the reasoning effort, disable thinking where supported, or choose a lighter model.
4
Provider-dependent limits. Maximum output is listed as 262,144 tokens by Volcano Engine but as 65,536 on at least one third-party host. Structured output also differs: one gateway reports JSON mode without strict schema enforcement, while another lists JSON schema. Workflows that depend on long single-pass generation or guaranteed schema conformance should validate outputs and confirm limits for their exact access route.
Best-Fit Workloads
Where this model earns its place
01
High-Volume Agent Pipelines
ByteDance describes Turbo as built for long-horizon agent workflows with multi-step tool use, and it supports tool calling and a reasoning mode. It is aimed at high-frequency enterprise calls where volume matters more than peak capability. That suits routine agent steps such as planning, tool selection and result checking. No Turbo-specific agent benchmark is published, so measure task success and keep a stronger model for steps that fail.02
Image and Video Understanding
Seed 2.1 Turbo accepts text, image and video input, which is less common among lower-cost tiers. It fits document pages, screenshots, product imagery and video clips that need a text answer, extraction or classification. BytePlus lists visual understanding and GUI agent capability for the model. Output is text only, and no vision benchmark scores are published, so test accuracy on your own media.03
Cost-Aware Coding Agents
ByteDance positions the Seed 2.1 family for coding across full project cycles, and Turbo carries the same stated feature set as Pro at the lower-cost tier. A 262K window can hold substantial multi-file context. Turbo suits routine edits, test generation and code review at volume. Use Seed 2.1 Pro for the hardest engineering tasks, since Turbo's coding accuracy relative to Pro is not published.04
Long-Document Q&A
The 262,144-token window accommodates long reports, knowledge-base excerpts and large prompt scaffolds in a single request, with reasoning available for multi-step questions. It suits internal knowledge assistants and document analysis where inputs fit below roughly 256K tokens. Longer corpora need retrieval or a larger-window model, and raising the response limit is necessary for long answers because the default is low.Integration
01
One API integration
02
Easy model switching
03
Flexible for production
04