ByteDance Seed · Released Jun 23, 2026Seed 2.1 Pro
Flagship ByteDance Seed 2.1 model for complex multimodal reasoning, coding, and agents.
- Capability
- —No ECI score yet
- Input
- $0.891per 1M tokens
- Output
- $4.45per 1M tokens
- Context
- 256K256K max output
What it costs
- Input
- $0.891per million tokens
- Output
- $4.45per million tokens
- Cached input
- $0.178per million tokens
- Blended (3:1)
- $1.78pricier than 68% of priced models
Typical monthly bills
| Monthly usage | Estimated cost |
|---|---|
| Side project2M input + 0.5M output tokens | $4.01 |
| Team assistant25M input + 5M output tokens | $44.53 |
| Production app250M input + 50M output tokens | $445.30 |
Official Volcengine Ark API price, as listed on models.dev.
Independent benchmarks
Epoch AI has not published a Capabilities Index score for Seed 2.1 Pro yet.
The details
- Lab
- ByteDance Seed
- Released
- Jun 23, 2026
- Context window
- 256,000 tokens
- Max output
- 256,000 tokens
- Inputs
- Text, Images, Video
- Output
- Text
- Reasoning
- Adjustable effort minimal · low · medium · high · xhigh · max
- Tool calling
- Yes
- Structured output
- Yes
- Weights
- Proprietary
- API model ID
doubao-seed-2-1-pro-260628on Volcengine Ark- Availability
- 2 API providerslisted on models.dev
More from ByteDance Seed
About Seed 2.1 Pro
How much does Seed 2.1 Pro cost?
Seed 2.1 Pro costs $0.891 input / $4.45 output per million tokens (official Volcengine Ark API price). Cached input is $0.178 per million tokens. At a 3:1 input-to-output mix that is $1.78 per million tokens, more expensive than 68% of the 360 priced models we track.
What is the context window of Seed 2.1 Pro?
Seed 2.1 Pro accepts up to 256,000 tokens per request and can write up to 256,000 tokens in one response.
How good is Seed 2.1 Pro?
Epoch AI has not published a Capabilities Index score for Seed 2.1 Pro yet.
Is Seed 2.1 Pro open source?
No. Seed 2.1 Pro is proprietary; you use it through Volcengine Ark’s API or partner platforms.
What inputs does Seed 2.1 Pro support?
Seed 2.1 Pro accepts text, images and video and replies in text. It is a reasoning model with minimal, low, medium, high, xhigh and max effort settings, supports tool calling and can return structured JSON output.
When was Seed 2.1 Pro released?
ByteDance Seed released Seed 2.1 Pro on Jun 23, 2026.
What are the best alternatives to Seed 2.1 Pro?
The closest current models from other labs on capability, price and release date are MiMo-V2.5-Pro-UltraSpeed (Xiaomi, $1.30 / $2.61), Sakana Namazu (Sakana AI, $0.95 / $4.00), DeepSeek V4 Pro (DeepSeek, $1.32 / $3.00) and LongCat-2.0 (Meituan (LongCat), $0.75 / $2.95).