Solar Open Models by Upstage
Upstage releases · 3 in the last 12 months · this family litChangelog →
1 model2026Up to 1.05m ctx
Last refreshed 2026-10-05. Next refresh: weekly.
Details
ResearcherUpstage
LicenseUpstage Solar License
Commercial useCommercial use: permitted
Models1
Released2026
Max context1.05m
Capabilities
ReasoningAll models
JSON / Tool useAll models
About
Upstage's Solar Open line of open-weight sovereign Korean foundation models, released under the Upstage Solar License (Apache 2.0 plus a Solar-branding requirement for derivative models). Solar Open 2 (250B total / 15B active, hybrid linear/softmax-attention MoE, 1M context) followed Solar Open 100B (December 2025, not yet seeded).
Decision facts
- Best fit
- reasoningJSON / Tool usecoding
- Capability starting point
- Solar Open 2 with 1.05m context and reasoning and JSON / Tool use
- Lowest tracked input
- Not tracked
- Closest related family
- Solar Decide
Current Variants
Use-when guidance is based on each model's tracked capabilities, context window, release date, and replacement status.
1 in view
Solar Open 2Current
Use when the workload needs 1.05m context, reasoning, and JSON / Tool use.
2026-071.05m contextreasoningJSON / Tool use
| Model | Use when | Released | Signals | Status |
|---|---|---|---|---|
| Solar Open 2 | Use when the workload needs 1.05m context, reasoning, and JSON / Tool use. | 2026-07 | 1.05m contextreasoningJSON / Tool use | Current |
Release Timeline
1 release group2026-07
1 current
Solar Open 2
Current1.05m contextreasoningJSON / Tool use
Specifications(1 models)
| Model | Released | Context | Parameters | Reasoning | JSON / Tool use |
|---|---|---|---|---|---|
| Solar Open 2 | 2026-07 | 1.05m | 250B (15B activated) | Yes | Yes |
