ByteDanceText Generation/v1/ai/chat

Seed 2.1 Turbo API

Access Seed 2.1 Turbo through one API key. ByteDance Multimodal Coding Agent.

Seed 2.1 Turbo is a multimodal model from ByteDance Seed for coding and long-horizon agent workflows, suited for end-to-end software delivery, multi-step task execution and understanding visual and video input. Seed 2.1 Turbo is a capable, cheap engine for coding agents that also need to read screenshots and recordings, and it succeeds Seed 2.0 Lite as the seed alias target.

Full Docs Get API Key

Takes 30 seconds.

Seed 2.1 Turbo API pricing

Pay per request from your YepAPI balance — no subscription, no monthly minimum. Prices updated September 27, 2026.

Token type	Price
Input	$0.74 / 1M tokens
Output	$3.69 / 1M tokens
Context window	262K tokens

What it costs	Per job	Per 1,000
Chat reply1K input + 500 output tokens	$0.0026	$2.58
RAG answer8K input + 800 output tokens	$0.0089	$8.87
Agent step with tools30K input + 2K output tokens	$0.03	$29.58
Long document summary100K input + 2K output tokens	$0.081	$81.38

4,900+

Developers

2.3M+

API calls served

184

Endpoints

$0.01

Per call

Yep, that's it.

Try it live

Send a message and see Seed 2.1 Turbo respond in real time.

POST/v1/ai/chatbytedance-seed/seed-2-1-turbo

Message *

Max Tokens

Maximum tokens in the response.

Stream

Real-time tokens

Hit "Send Request" to see the response

Seed 2.1 Turbo specs

Provider	ByteDance
Model ID	bytedance-seed/seed-2-1-turbo
Endpoint	/v1/ai/chat
Type	Text Generation
Context window	262K tokens
Max output	236K tokens
Reasoning	No
OpenAI-compatible	Yes — /v1/ai/chat/completions

How to get a Seed 2.1 Turbo API key

1
Create an account
Sign up at yepapi.com with Google or email. It takes about 30 seconds.
2
Create an API key
Open the dashboard, go to API Keys and create a key. Copy it — it starts with yep_sk_.
3
Call Seed 2.1 Turbo
Send a request to /v1/ai/chat with the x-api-key header and model "bytedance-seed/seed-2-1-turbo".
4
Pay as you go
Usage is billed per request from your balance. Top up any amount; there is no subscription.

Strengths

✓

Built for coding agents

Tuned for end-to-end software delivery and multi-step execution.

✓

Visual and video input

Accepts text, images and video.

✓

262K context, 236K output

Handles up to 262,144 input tokens and returns up to 235,929 output tokens per call.

✓

Low cost

$0.74 per 1M input and $3.69 per 1M output tokens.

Quick start

Copy this snippet and start making calls with Seed 2.1 Turbo.

const res = await fetch('https://api.yepapi.com/v1/ai/chat', {
  method: 'POST',
  headers: {
    'x-api-key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "model": "bytedance-seed/seed-2-1-turbo",
    "messages": [
      {
        "role": "user",
        "content": "Explain API gateways in 2 sentences."
      }
    ],
    "maxTokens": 256
  }),
});
const { data } = await res.json();
console.log(data.message.content);

Seed 2.1 Turbo vs similar models

Every model below runs on the same API key — switch by changing the model ID.

Model	Provider	Price	Context
Seed 2.1 Turbo	ByteDance	$0.74 in / $3.69 out per 1M	262K
Seed 1.6 Flash	ByteDance	$0.11 in / $0.44 out per 1M	262K
Seed 2.0 Mini	ByteDance	$0.15 in / $0.59 out per 1M	262K
Seed 2.0 Lite	ByteDance	$0.37 in / $2.95 out per 1M	262K
Seed 1.6	ByteDance	$0.37 in / $2.95 out per 1M	262K
Seed-2.0-Code	ByteDance	$0.74 in / $4.43 out per 1M	262K
Nemotron 3 Super	NVIDIA	$0 in / $0 out per 1M	262K
Qwen3.7 Flash	Qwen	$0.04 in / $0.19 out per 1M	1M

Why use Seed 2.1 Turbo through YepAPI?

✓One API key for all models — no separate accounts

✓OpenAI SDK compatible — just change the base URL

✓No monthly minimums — pay per token

✓Switch models with one line of code

✓Full provider passthrough — citations, search results, and all extras included

✓Streaming and non-streaming support on every model

✓Works with Cursor, Claude, LangChain, and any LLM tool

✓Unified billing across all providers

Seed 2.1 Turbo API — pricing, context window & access

Seed 2.1 Turbo is a multimodal model from ByteDance Seed for coding and long-horizon agent workflows, suited for end-to-end software delivery, multi-step task execution and understanding visual and video input. It pairs a 262,144-token context window with up to 235,929 output tokens per response, at $0.74 per 1M input and $3.69 per 1M output tokens through YepAPI.

Through YepAPI you call Seed 2.1 Turbo on an OpenAI-compatible endpoint with a single key — the same key that reaches GPT-6, Claude, Gemini, Grok and the SEO, SERP and scraping APIs. Input: text, images, video.

What is Seed 2.1 Turbo?

Seed 2.1 Turbo is a multimodal model from ByteDance Seed for coding and long-horizon agent workflows, suited for end-to-end software delivery, multi-step task execution and understanding visual and video input. It offers a 262,144-token context window and up to 235,929 output tokens at $0.74 / $3.69 per 1M tokens. It accepts text, images, video as input, handles up to 262,144 tokens of context and returns up to 235,929 output tokens per call.

Build with Seed 2.1 Turbo via YepAPI

YepAPI serves Seed 2.1 Turbo on the OpenAI-compatible /v1/ai/chat endpoint. Point your base URL at YepAPI, add your key, and set the model string to seed-2-1-turbo (or the full bytedance-seed/seed-2-1-turbo). Function calling, structured outputs and reasoning settings pass straight through, and switching to any other model on the platform is a one-string change per request.

Seed 2.1 Turbo API pricing — $0.74 / 1M input, $3.69 / 1M output

Seed 2.1 Turbo costs $0.74 per 1M input tokens and $3.69 per 1M output tokens through YepAPI, pay per token with no minimums. Failed calls are never charged, and every request is itemised in your dashboard API Logs so you can see exactly what a very long response cost.

Seed 2.1 Turbo use cases

Seed 2.1 Turbo is a capable, cheap engine for coding agents that also need to read screenshots and recordings, and it succeeds Seed 2.0 Lite as the seed alias target.

Start generating in 30 seconds

Pay per call, no subscriptions.

Get API Key

What developers say

“Switched from SerpAPI and cut our SERP costs by 80%. Same data quality, way simpler billing.”
Marcus T.
SEO Platform Founder

“One API key for AI models, SERP data, and web scraping. Saved us from managing 4 separate providers.”
Priya S.
Full-Stack Developer

“The $5 free credit let us prototype our entire rank tracking feature before committing. No other API does that.”
Jake R.
Indie Hacker

Frequently asked questions

Seed 2.1 Turbo costs $0.74 per 1M input tokens and $3.69 per 1M output tokens through YepAPI, billed per request with no monthly fee. For example, a chat reply (1K input + 500 output tokens) costs about $0.0026.

Sign up at yepapi.com (Google or email, about 30 seconds), open the dashboard and create an API key. The same key works for Seed 2.1 Turbo and every other model — no separate ByteDance account or waitlist.

Use "bytedance-seed/seed-2-1-turbo" as the model on /v1/ai/chat. The short alias "seed-2-1-turbo" also works.

Yes. Point the OpenAI SDK at https://api.yepapi.com/v1/ai with your YepAPI key and set model to "bytedance-seed/seed-2-1-turbo". Streaming works the same way, so existing OpenAI code only needs the base URL and key changed.

Seed 2.1 Turbo supports a 262K token context window with up to 236K output tokens per request.