# Seed 2.1 Pro

> Seed 2.1 Pro is a proprietary language model from ByteDance Seed, released on 23 Jun 2026. It accepts text, images and video and generates text, with a 256K-token context window and up to 256K output tokens per response.

Source page: https://www.aimodel.directory/models/seed-2-1-pro
Last verified: 4 Oct 2026

## Specifications

- **Developer:** ByteDance Seed
- **Release date:** 23 Jun 2026 (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/volcengine/models/doubao-seed-2-1-pro-260628.toml)
- **Status:** Generally available (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/volcengine/models/doubao-seed-2-1-pro-260628.toml)
- **Weights:** Proprietary (API only) (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/volcengine/models/doubao-seed-2-1-pro-260628.toml)
- **Context window:** 256K (256,000 tokens) (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/volcengine/models/doubao-seed-2-1-pro-260628.toml)
- **Max output:** 256K tokens (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/volcengine/models/doubao-seed-2-1-pro-260628.toml)
- **Input:** Text, images and video (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/volcengine/models/doubao-seed-2-1-pro-260628.toml)
- **Output:** Text (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/volcengine/models/doubao-seed-2-1-pro-260628.toml)
- **Reasoning mode:** Yes (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/volcengine/models/doubao-seed-2-1-pro-260628.toml)
- **Tool calling:** Yes (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/volcengine/models/doubao-seed-2-1-pro-260628.toml)
- **Structured output:** Yes (source: models.dev, https://github.com/sst/models.dev/blob/dev/providers/volcengine/models/doubao-seed-2-1-pro-260628.toml)

## API pricing (USD per 1M tokens)

| Provider | Input | Output | Cached input | Context |
|---|---|---|---|---|

## FAQ

### What is the context window of Seed 2.1 Pro?

Seed 2.1 Pro has a context window of 256,000 tokens (256K) and can generate up to 256,000 tokens in a single response, according to models.dev.

### Is Seed 2.1 Pro open source?

No. Seed 2.1 Pro is a proprietary model; ByteDance Seed has not released its weights.

### When was Seed 2.1 Pro released?

ByteDance Seed released Seed 2.1 Pro on 23 Jun 2026, according to models.dev.

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Data licensed CC BY 4.0. Cite as: AI Model Directory, "Seed 2.1 Pro", https://www.aimodel.directory/models/seed-2-1-pro