ByteDance Seed

Seed Character

Generally availableProprietary256K contextReasoning

Summary

Seed Character 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.

ByteDance Seed model optimized for character-driven dialogue and consistent conversational behavior

Last verified 4 Oct 2026. Every figure on this page links to its source.

Specifications

DeveloperByteDance Seed
Release date23 Jun 2026 [models.dev]
StatusGenerally available [models.dev]
WeightsProprietary (API only) [models.dev]
Context window256K (256,000 tokens) [models.dev]
Max output256K tokens [models.dev]
InputText, images and video [models.dev]
OutputText [models.dev]
Reasoning modeYes [models.dev]
Tool callingYes [models.dev]
Structured outputYes [models.dev]

Seed Character API pricing by provider

USD per million tokens. Sorted by input price.

We do not currently track a paid API listing for this model.

Frequently asked questions

What is the context window of Seed Character?

Seed Character 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 Character open source?

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

When was Seed Character released?

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

Change history

No changes detected since we started tracking this model. We re-check every source daily.

Sources