Moduck

Bytedance Seed: Seed 2.1 Pro

Flagship ByteDance Seed 2.1 model for complex multimodal reasoning, coding, and agents

Model lab
Bytedance Seed
Model family
seed
Modalitiestext, image, video → text
Context window256,000
Maximum output256,000
InputUSD 0.56576 / 1M tokens
OutputUSD 2.8288 / 1M tokens

Quickstart

Use your Moduck API Key, set the API base URL to https://api.moduck.ai/v1, and set the model parameter to bytedance-seed/seed-2.1-pro.

import os
import requests

base_url = "https://api.moduck.ai/v1"
api_key = os.environ["MODUCK_API_KEY"]
model_id = "bytedance-seed/seed-2.1-pro"

response = requests.post(
    f"{base_url}/chat/completions",
    headers={
        "Authorization": f"Bearer {api_key}",
        "Content-Type": "application/json",
    },
    json={
        "model": model_id,
        "messages": [{"role": "user", "content": "Hello!"}],
        "stream": False,
    },
    timeout=60,
)
response.raise_for_status()
print(response.json())

Use the familiar OpenAI-style chat request format to make model integration easier.

Seed 2.1 Pro API Pricing

TypePrice information
InputUSD 0.56576 / 1M tokens
OutputUSD 2.8288 / 1M tokens
Cached inputUSD 0.11328 / 1M tokens
Cache writeUSD 0.0016 / 1M tokens

Performance

Measured on the Moduck gateway across live traffic, hour by hour over the last 24 hours. Time to first token is how long before anything appears; throughput is how fast the answer is written after that; end-to-end latency is the whole round trip. Figures are medians unless the card says otherwise.

Performance trends

Throughput88.4 tok/sCurrent
Time to first token1.4 sCurrent
End-to-end latency7.0 sCurrent
Throughput
Current88.4 tok/s
Window average89.8 tok/s
Time to first token
Current1.4 s
Window average1.4 s
End-to-end latency
Current7.0 s
Window average7.5 s
Tail latency (P99)
Current15.8 s
Window average16.7 s
Prompt cache hit rate
Current26.1%
Window average23.6%
Error rate
Current2.1%
Window average0.2%

Availability

Uptime is the share of time at least one provider serving this model responded. Availability is stricter: the share of requests actually served. A provider that answers but fails part of the traffic lowers availability without lowering uptime. Both cover the last three days.

Uptime100%At least one provider responded
Availability100%Requests actually served
Error rate0%Share of failed requests
Served requests, hour by hour
24 hours agoNow

Seed 2.1 Pro Compare models

ModelInput priceOutput priceContext windowCapabilities
Seed 2.1 ProThis pageUSD 0.56576 / 1M tokensUSD 2.8288 / 1M tokens256,000Text output · Reasoning · Tool calling
Seed 2.1 TurboUSD 0.28288 / 1M tokensUSD 1.41568 / 1M tokens256,000Text output · Reasoning · Tool calling
Seed CharacterUSD 0.095 / 1M tokens · Base context tier (boundary 32000 tokens)USD 0.237496 / 1M tokens · Base context tier (boundary 32000 tokens)256,000Text output · Reasoning · Tool calling
Seed EvolvingUSD 0.7072 / 1M tokensUSD 3.536 / 1M tokens256,000Text output · Reasoning · Tool calling
Seed 2.0 CodeUSD 0.379992 / 1M tokens · Base context tier (boundary 32000 tokens)USD 1.899952 / 1M tokens · Base context tier (boundary 32000 tokens)262,144Text output · Reasoning · Tool calling

Model specifications

Input
text, image, video
Output
text
Context window
256,000
Maximum output
256,000
Release date
2026-06-23
Attachments
Yes
Reasoning
Yes
Tool calling
Yes
Structured output
Yes
Temperature setting
Yes
Open weights
No

Frequently asked questions

What is Seed 2.1 Pro for?

Flagship ByteDance Seed 2.1 model for complex multimodal reasoning, coding, and agents

What inputs and outputs does Seed 2.1 Pro support?

Recorded inputs: text, images, video; outputs: text.

How is Seed 2.1 Pro priced?

The pricing table shows the current recorded Moduck price. For example: Input USD 0.56576 / 1M tokens; Output USD 2.8288 / 1M tokens. See the pricing table for all units, variants, and conditions.

What specifications are recorded for Seed 2.1 Pro?

Current model records list Context window 256,000 tokens; Maximum output 256,000 tokens.

What model parameter does the Quickstart use?

The example uses bytedance-seed/seed-2.1-pro. This value comes from the page identifier and is not confirmed as a callable Moduck public ID.

Can I call this model through the Moduck API now?

This page has no verified Moduck API call for this model. A Quickstart example or reserved ID does not establish access; check the models available to your account.