Solar Pro 4
General purposeToolsUpstage · Released August 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...
Facts and pricing
- Provider
- Upstage
- Context window
- 524K tokens
- Input price
- 0.33 credits / 1M tokens ($0.030 raw)
- Output price
- 1.3 credits / 1M tokens ($0.12 raw)
- Vision (image input)
- No
- Tool calling
- Yes
- Extended reasoning
- No
Credits are what Zeplik bills: 1 credit = $0.10, computed from the raw provider rate with a 1.10x margin. Raw prices shown per 1M tokens.
Try Solar Pro 4 now
What Solar Pro 4 is best for
- Balanced everyday work: writing, questions, brainstorming and summarization
- Very long documents and codebases: a 524K-token window fits entire books or repositories in one conversation
- Tool use and agents: reliably calls functions, so it can search, run skills and drive workflows
Upstage family
| Model | Context | Input cr/M | Output cr/M | Released |
|---|---|---|---|---|
| Solar Pro 4 | 524K | 0.33 | 1.3 | August 2026 |
| Solar Pro 3 | 131K | 1.7 | 6.6 | January 2026 |
Frequently asked questions
- What is Solar Pro 4?
- Solar Pro 4 is an AI model by Upstage. 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...
- How much does Solar Pro 4 cost on Zeplik?
- Input tokens cost 0.33 credits per million and output tokens 1.3 credits per million (1 credit = $0.10; the raw provider rates are $0.030 and $0.12 per million). New accounts start with free credits.
- How long can a conversation with Solar Pro 4 be?
- Solar Pro 4 has a 524K-token context window (524,288 tokens), which covers the conversation plus any documents you attach.
- Does Solar Pro 4 support images and tools?
- Solar Pro 4 is text-only and supports tool calling.
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More you can do with Solar Pro 4
- 465 AI skillsReady-to-run expert methods for writing, data, code and more, each running on Solar Pro 4 or any model you pick.
- 997 integrationsConnect Gmail, Slack, GitHub, Notion and hundreds more so the assistant can work in your apps.
- Simple pricingPlus, Pro and Max plans with a monthly credit allowance that works across every model.