ByteDance Seed 1.8 API

ByteDance Seed 1.8 is a large language model with a 256K context window optimized for long-context reasoning and generation.

Modalities
Image, TextText
In / Out price
$0.25/$2per 1M
Context window
250K tokens
Released
Jan 12, 2026

ByteDance Seed 1.8 overview

The pelican test: one prompt, every text model, unedited SVG output from Nov 3, 2026.

SVG of a pelican riding a bicycle, written by ByteDance Seed 1.8 through AI/ML API

ByteDance Seed 1.8 specs

Model ID
bytedance/seed-1-8
Developer
ByteDance
Context window
256,000 tokens
Max output
224,000 tokens
Input
Image, Text
Output
Text
API
OpenAI-compatible, base URL https://api.aimlapi.com/v1

ByteDance Seed 1.8 is a large language model with a 256K context window optimized for long-context reasoning and generation.

Coding and code review
Generate, debug, and review code across languages, reading whole files or repos in a single prompt.

Agentic and multi-step workflows
Reliable tool-calling and instruction-following suit agent loops that plan, call tools, and iterate.

Long-document analysis
Summarize and extract from contracts, papers, and reports without aggressive chunking.

Use cases

Seed 1.8 is documented as suited to information retrieval, code generation and execution, and GUI interaction.

It is also documented for complex multi-step workflows and other agentic tasks that require persistent interaction across multiple steps.

The model is also described as applicable to educational tutoring and customer service Q&A.

It is further documented for information processing, intent recognition, and information extraction.

Capabilities

  • Function calling
  • Streaming
  • Structured outputs

ByteDance Seed 1.8 API pricing

ByteDance Seed 1.8 pricing in US dollars
UsagePriceUnit
Input$0.251M tokens
Output$21M tokens

Prices from the AI/ML API price list, checked on Nov 4, 2026.

ByteDance Seed 1.8 vs other models: token prices

AI/ML API input and output rates for 5 models, per million tokens.

AI/ML API model prices in USD per million tokens
ModelInputOutput
ByteDance Seed 1.8$0.25$2
Dola-Seed 2.0 Mini$0.1$0.4
Dola-Seed 2.0 Lite$0.25$2
Seed 2.1 Turbo$0.529$2.65
Seed 2.0 Code$0.529$3.17

How to use the ByteDance Seed 1.8 API

View docs

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key
export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/chat/completions' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "bytedance/seed-1-8",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'

Related articles

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ByteDance Seed 1.8 FAQ

What is the context window of ByteDance Seed 1.8?

ByteDance Seed 1.8 has a 256,000 tokens context window and can return up to 224,000 tokens.

What inputs and outputs does ByteDance Seed 1.8 support?

ByteDance Seed 1.8 takes image, text as input and returns text.

What is the model ID for ByteDance Seed 1.8?

Use bytedance/seed-1-8 as the model id. Requests go to https://api.aimlapi.com/v1/chat/completions.

How much does ByteDance Seed 1.8 cost?

ByteDance Seed 1.8 costs $0.25 input and $2 output per 1M tokens on AI/ML API, billed as you go with no subscription.

Does ByteDance Seed 1.8 support streaming?

Yes, ByteDance Seed 1.8 can stream responses as they are generated.

Can ByteDance Seed 1.8 read images?

Yes, ByteDance Seed 1.8 accepts image input alongside text.

Who created ByteDance Seed 1.8?

ByteDance Seed 1.8 was built by ByteDance.

What capabilities does ByteDance Seed 1.8 support?

It supports function calling, streaming responses, and structured outputs, along with parallel tool calls and vision input.

Start building with ByteDance Seed 1.8

ByteDance Seed 1.8 API

bytedance/seed-1-8

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key
export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/chat/completions' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "bytedance/seed-1-8",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'