Solar Mini 4

About

Solar Mini 4 is Upstage’s compact language model, a mixture-of-experts model with 35B parameters and 3B active parameters. It is built for agentic use cases where response... The model accepts text and produces text, with listed reasoning and tool capabilities. Its context window is 524,288 tokens, and its maximum output is 131,072 tokens. Pricing is USD 0.05 per 1M input tokens and USD 0.2 per 1M output tokens. Solar Mini 4 was released on 2026-09-23. Its model ID is upstage/solar-mini4, and its listed family is upstage. Upstage is both its maker and lab. The available details point to a text-only model with tools and reasoning for agentic applications, alongside a defined context limit and per-token pricing for planning usage.

Who it is for

Solar Mini 4 suits teams considering a text model for agentic use cases, especially where tool use or reasoning is relevant. Its listed input and output prices can support token-cost planning.

Details

Lab

Upstageopenrouter.ai · 3 Oct 2026

Context

524Kopenrouter.ai · 3 Oct 2026

Input price

$0.05 / 1Mopenrouter.ai · 3 Oct 2026

Output price

$0.2 / 1Mopenrouter.ai · 3 Oct 2026

Max output

131,072 tokensopenrouter.ai · 3 Oct 2026

Inputs

textopenrouter.ai · 3 Oct 2026

Open weights

Noopenrouter.ai · 3 Oct 2026

Listed on Inferse

• Longest-Context Models in 2026466 listed
• Newest Models in 2026466 listed
• Cheapest Language Models in 2026444 listed
• Models with Tool Calling in 2026398 listed
• Reasoning Models in 2026332 listed
• Upstage Models: Pricing per 1M Tokens and Context (2026)3 listed

Sources

• openrouter.ai/upstage/solar-mini4· checked 3 Oct 2026