Solar Mini 4 is a 35B MoE model priced at $0.05 per million input tokens on OpenRouter

Upstage’s Solar Mini 4 is available on OpenRouter as a 35B mixture-of-experts model with 3B active parameters and a 524K context window. It supports tool calling and structured outputs, with optional reasoning, and OpenRouter positions it for fast, low-cost agentic work.

Input is priced at $0.05 per million tokens and output at $0.20 per million tokens. Specifications are on the Solar Mini 4 page.