Solar Mini 4
Solar Mini 4 is Upstage's compact, cost-efficient language model, a 35B-parameter mixture-of-experts with 3B active parameters and a 524K context window.
Specifications
| Lab | Upstage |
|---|---|
| Context window | 524.3K tokens |
| Input price | $0.05/1M |
| Output price | $0.20/1M |
| Release | Sep 2026 |
Strengths
- 35B MoE model with 3B active parameters
- 524K context window
- Low token pricing for agentic workloads
Weaknesses
- Smaller active capacity than frontier models
- Limited independent benchmark coverage at launch
Best for
- Cost-sensitive agent workflows
- Long-context coding and document tasks
- High-volume text generation
In Depth: Solar Mini 4
Summary
Solar Mini 4 is an AI model from Upstage.
Released in Sep 2026. It takes text input and produces text output, with a context window of 524.3K tokens. Input pricing is $0.05 per 1M tokens and output is $0.20 per 1M tokens on OpenRouter.