Name: ByteDance Seed 1.8 API
Brand: ByteDance

Overview

What is 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.

Technical Specifications
- Supported inputs: Image, Text
- Output: Text
- Context window: 256,000 tokens / Max output: 224,000 tokens
- Endpoint: /chat/completions

Performance Benchmarks
[embed]

Seed 1.8 API Pricing
- Input: $0.325 / 1M tokens
- Output: $2.6 / 1M tokens

Where to Use Seed 1.8

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.

Code Sample
[embed]

Uptime and performance

Uptime (7d): 100%

Measured on the AI/ML API gateway across live traffic. Figures are medians unless stated. Last updated 2026-10-12.

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.

How to use ByteDance Seed 1.8 API

Install any OpenAI-compatible SDK, point it at api.aimlapi.com/v1, and set the model to bytedance/seed-1-8.

import requests

r = requests.post(
    "https://api.aimlapi.com/v1/chat/completions",
    headers={"Authorization": "Bearer " + AIMLAPI_KEY},
    json={
      "model": "bytedance/seed-1-8",
      "messages": [
        {
          "role": "user",
          "content": "Hello!"
        }
      ]
    },
)
print(r.json())

const r = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "bytedance/seed-1-8",
    "messages": [
      {
        "role": "user",
        "content": "Hello!"
      }
    ]
  }),
});
console.log(await r.json());

curl -X POST 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":"Hello!"}]}'

OpenAI-compatible — swap the base URL and it works with your existing SDK.