# Solar Mini 4

> Solar Mini 4 is a language model from Upstage, released on 23 Sept 2026. It accepts text and generates text, with a 524K-token context window and up to 131K output tokens per response. As of 4 Oct 2026, the lowest listed API price is $0.05 per million input tokens and $0.20 per million output tokens (OpenRouter), across 1 provider we track.

Source page: https://www.aimodel.directory/models/solar-mini4
Last verified: 4 Oct 2026

## Specifications

- **Developer:** Upstage
- **Release date:** 23 Sept 2026 (source: OpenRouter, https://openrouter.ai/upstage/solar-mini4)
- **Status:** Generally available
- **Context window:** 524K (524,288 tokens) (source: OpenRouter, https://openrouter.ai/upstage/solar-mini4)
- **Max output:** 131K tokens (source: OpenRouter, https://openrouter.ai/upstage/solar-mini4)
- **Input:** Text (source: OpenRouter, https://openrouter.ai/upstage/solar-mini4)
- **Output:** Text (source: OpenRouter, https://openrouter.ai/upstage/solar-mini4)
- **Reasoning mode:** Yes (source: OpenRouter, https://openrouter.ai/upstage/solar-mini4)
- **Tool calling:** Yes (source: OpenRouter, https://openrouter.ai/upstage/solar-mini4)
- **Structured output:** Yes (source: OpenRouter, https://openrouter.ai/upstage/solar-mini4)

## API pricing (USD per 1M tokens)

| Provider | Input | Output | Cached input | Context |
|---|---|---|---|---|
| OpenRouter | $0.05 | $0.20 | $0.005 | 524K |

## FAQ

### What is the context window of Solar Mini 4?

Solar Mini 4 has a context window of 524,288 tokens (524K) and can generate up to 131,072 tokens in a single response, according to OpenRouter.

### How much does the Solar Mini 4 API cost?

Solar Mini 4 is listed from $0.05 per million input tokens and $0.20 per million output tokens (OpenRouter). Prices last verified 4 Oct 2026.

### When was Solar Mini 4 released?

Upstage released Solar Mini 4 on 23 Sept 2026, according to OpenRouter.

---
Data licensed CC BY 4.0. Cite as: AI Model Directory, "Solar Mini 4", https://www.aimodel.directory/models/solar-mini4