Solar Mini 4 vs Union Alpha
Specs, per-token pricing, and live benchmark scores — refreshed daily from our benchmark database.
Specs & pricing
| Solar Mini 4 | Union Alpha | |
|---|---|---|
| Company | Upstage | Stealth |
| Released | Sep 2026 | Sep 2026 |
| Context window | 524K | 262K |
| Input /1M tokens | $0.05 | free |
| Output /1M tokens | $0.2 | free |
| Open weights | No | No |
Benchmarks
| Benchmark | Solar Mini 4 | Union Alpha |
|---|---|---|
| GPQA | — | 90.9% |
Scores come from published leaderboards and official model cards (sources listed on the benchmarks page) and refresh daily. Pricing via vendor pages and OpenRouter.