Question 1

What is Solar Pro 4?

Accepted Answer

Solar Pro 4 is a model from Upstage, released on Aug 10, 2026. Solar Pro 4 is Upstage's cost-efficient large language model, featuring a 524K context window. It is built for long-horizon tasks and agentic workflows, with strong capabilities in office productivity, document-intensive...

Question 2

How much does Solar Pro 4 cost?

Accepted Answer

On the Respan gateway, input starts at $0.09 per 1M tokens on OpenRouter, and output starts at $0.36 per 1M tokens on OpenRouter, after gateway discounts.

Question 3

Which providers serve Solar Pro 4 on Respan?

Accepted Answer

Solar Pro 4 is served by OpenRouter.

Question 4

What is Solar Pro 4's context window?

Accepted Answer

Solar Pro 4 accepts up to 524K tokens of context.

Question 5

How do I use Solar Pro 4 with the Respan gateway?

Accepted Answer

Point any OpenAI-compatible SDK at https://api.respan.ai/api/ with your Respan API key and set the model to "solar-pro4". To set it up with a coding agent, copy the agent setup prompt at the top of this page.

Question 6

How fast is Solar Pro 4?

Accepted Answer

Over the last 30 days of requests through the Respan gateway, the fastest provider was OpenRouter at 13 tokens per second, and the lowest response latency was 0.8 seconds on OpenRouter. Speed varies with request size and provider.

Question 7

How does Solar Pro 4 score on benchmarks?

Accepted Answer

Solar Pro 4 has 4 published benchmark scores, including Artificial Analysis Intelligence Index 42 and LMArena Elo 1386. Each score links to where it was published; the data is collected by llmmetric.com.

Solar Pro 4

Providers

Pricing

Cost by volume

Throughput and latency

Output speed

Response latency

Benchmarks

Certified where it counts.

Reasoning1

Arena3

Apps

Solar Pro 4 FAQ

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