Hy4 preview

Name: Tencent Hy4 preview
Price: 0.834 USD
Availability: InStock
Author: Tencent

tencent/hy4-preview

Hy4 preview is Tencent Hunyuan's open-source preview of its Hy4 generation, a mixture-of-experts language model with 770B total and 49B active parameters and a context window exceeding 1M tokens. Tencent built it for real-world productivity: long-context software development and front-end work, office and financial analysis, game prototyping and scientific research. Tencent follows a preview-first approach, with official Hy4 releases to come after this model.

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Input price: $0.83USD / 1M tokens
Output price: $2.50USD / 1M tokens
Context window: 1M
Max output: 64K

Production route

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Playground

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Prompt

1M context64K max output

Input$0.83/MOutput$2.50/MCache read$0.04/M

OutputReady

Your response will appear here

Choose an example or write a prompt, then click Run.

Model card

Specifications

Pricing

Input: $0.83 / 1M tokens
Output: $2.50 / 1M tokens
Cache read: $0.04 / 1M tokens

Context & modalities

Context window: 1,048,576 tokens
Max output: 64,000 tokens
Input: Text
Output: Text

Capabilities

Chat: Supported
Vision: Not supported
Reasoning: Supported
Structured output: Supported
Function calling: Supported
Audio input: Not supported

Access

Provider: Tencent
Model ID: tencent/hy4-preview
Execution: sync
Base URL: https://api.sandbase.ai
API: Chat Completions API
Endpoint: /v1/chat/completions

Start building

Send your first request

OpenAI-compatible endpoint with unified authentication and usage tracking.

Production API

Chat Completions API endpoint

https://api.sandbase.ai/v1/chat/completions

Model ID

tencent/hy4-preview

# The quoted heredoc keeps Unicode and shell metacharacters unchanged.
result=$(curl --fail-with-body --silent \
  -X POST "https://api.sandbase.ai/v1/chat/completions" \
  -H "Authorization: Bearer $SANDBASE_API_KEY" \
  -H "Content-Type: application/json" \
  --data-binary @- <<'SANDBASE_JSON'
{
  "model": "tencent/hy4-preview",
  "messages": [
    {
      "role": "user",
      "content": "Hello"
    }
  ],
  "max_tokens": 2048
}
SANDBASE_JSON
)
printf '%s\n' "$result"

Choose your model

Compare models

All language models

Model	Context	Input / 1M	Output / 1M	Released
Hy4 previewThis model `Tencent`	1M	$0.83	$2.50	Aug 28, 2026
Hy3 `Tencent`	256K	$0.13	$0.53	Jul 6, 2026

Questions

FAQ

How do I call Tencent Hy4 preview through SandBase?

Create a SandBase API key, then send requests with the model ID "tencent/hy4-preview" to Chat Completions API (/v1/chat/completions) at https://api.sandbase.ai. The request examples on this page show the exact payload.

How much does Tencent Hy4 preview cost?

$0.83 per 1M input tokens and $2.50 per 1M output tokens, billed per request from your SandBase balance. Discounts, when available, are shown in the pricing on this page.

What is the context window of Tencent Hy4 preview?

1M tokens of context, with up to 64K output tokens per response.

Which features does Tencent Hy4 preview support?

Tencent Hy4 preview supports reasoning, function calling, structured output. See Specifications above for the full list.

Do I need a separate Tencent account?

No. One SandBase API key and balance gives you access to Tencent Hy4 preview and the other models in the catalog; you do not need to sign up with Tencent separately.