# Solar Pro 4

> Solar Pro 4 is Upstage's cost-efficient large language model with a 524K context window, built for long-horizon tasks and agentic workflows.

**ID**: `upstage/solar-pro4`  
**Creator**: upstage  
**Category**: text  
**Context**: 524K tokens  
**Pricing**: $0.03 / $0.12 per 1M · billed by your provider (BYOK)  
**Released**: 2026-08-10  
**Web page**: https://anyrouter.dev/model/upstage/solar-pro4

**Input modalities**: text  
**Output modalities**: text  

**Capabilities**: chat, streaming, function-calling, reasoning

**Supported parameters**: max_tokens, temperature, top_p, stop, tools, tool_choice, response_format

## Usage

**Endpoint**: `POST https://anyrouter.dev/api/v1/chat/completions`

```bash
curl https://anyrouter.dev/api/v1/chat/completions \
  -H "Authorization: Bearer $ANYROUTER_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "upstage/solar-pro4",
  "messages": [
    {
      "role": "user",
      "content": "Say hi in 3 words."
    }
  ]
}'
```

## Providers

| Provider | Input | Output |
| --- | --- | --- |
| openrouter-byok | $0.03/M (list) | $0.12/M (list) |
| aihubmix-byok | $0.30/M (list) | $1.20/M (list) |

BYOK routes are billed by your own provider key — AnyRouter charges $0. Rates marked (list) are the provider's published list price.

## Source

- Upstream docs: https://www.upstage.ai/