Compare / head-to-head
Grok 4 Fast ReasoningvsSolar Open 2 250B-A15B
Solar Open 2 250B-A15B leads 2 of 2 shared benchmarks. Grok 4 Fast Reasoning has the larger context window (2M tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
0 – 2
Solar Open 2 250B-A15B leads
Cheaper per token
—
list price, input + output
Larger context
Grok 4 Fast Reasoning
2M tokens
Provider uptime (30d)
— · —
xAI · Upstage
Grok 4 Fast Reasoning
xAI · released 2025-09-19
text
Solar Open 2 250B-A15B
Upstage · released 2026-07-24
text
- Context
- 1M
- Max out
- —
- Input /1M
- —
- Output /1M
- —
- Cached /1M
- —
- Scores
- 16 · 5 core
Quality
Benchmark matrix
2 shared · 10 only Grok 4 Fast Reasoning · 14 only Solar Open 2 250B-A15B| Benchmark | Grok 4 Fast Reasoning | Solar Open 2 250B-A15B | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 2 | ||||
| GPQA Diamond | 85.7% ↗ | 86.3% ↗ | -0.6 pt | Solar Open 2 250B-A15B |
| Humanity's Last Exam (no tools) | 20% ↗ | 28.8% ↗ | -8.8 pt | Solar Open 2 250B-A15B |
| Only Grok 4 Fast Reasoning reports · 10 | ||||
| AIME 2025 | 92% ↗ | not reported | — | — |
| BrowseComp | 44.9% ↗ | not reported | — | — |
| BrowseComp (zh) | 51.2% ↗ | not reported | — | — |
| HMMT 2025 (no tools) | 93.3% ↗ | not reported | — | — |
| LiveCodeBench (Jan-May) | 80% ↗ | not reported | — | — |
| Reka Research Eval | 66% ↗ | not reported | — | — |
| Search Arena Elo | 1163 ↗ | not reported | — | — |
| SimpleQA | 95% ↗ | not reported | — | — |
| X Bench Deepsearch (zh) | 74% ↗ | not reported | — | — |
| X Browse | 58% ↗ | not reported | — | — |
| Only Solar Open 2 250B-A15B reports · 14 | ||||
| SWE-bench Verified | not reported | 70.4% ↗ | — | — |
| MMLU-Pro | not reported | 86.2% ↗ | — | — |
| AIME 2026 | not reported | 95.7% ↗ | — | — |
| AA-LCR | not reported | 62.3% ↗ | — | — |
| APEX-Agents | not reported | 16.6% ↗ | — | — |
| ArtifactsBench | not reported | 55.9% ↗ | — | — |
| GDPval-AA v2 | not reported | 1128 ↗ | — | — |
| HMMT 2026-02 | not reported | 93.9% ↗ | — | — |
| IFBench | not reported | 80% ↗ | — | — |
| LiveCodeBench v6 | not reported | 92.4% ↗ | — | — |
| MCP Atlas | not reported | 58.2% ↗ | — | — |
| Multi-Challenge | not reported | 61% ↗ | — | — |
| Tau3-Bench (banking) | not reported | 19.6% ↗ | — | — |
| Terminal Bench Hard | not reported | 28.3% ↗ | — | — |
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Grok 4 Fast Reasoning minus Solar Open 2 250B-A15B in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing
Side by side
Official pricing pages and model cards| Spec | Grok 4 Fast Reasoning | Solar Open 2 250B-A15B | Edge |
|---|---|---|---|
| Context window | 2M tokens | 1M tokens | Grok 4 Fast Reasoning |
| Max output | — | — | — |
| Input price / 1M | $0.2 ↗ | — | — |
| Output price / 1M | $0.5 ↗ | — | — |
| Cached input / 1M | $0.05 ↗ | — | — |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $0.7 | — | — |
| Modalities | text | text | Tie |
| Released | 2025-09-19 | 2026-07-24 | — |
| Cited benchmark scores | 12 | 16 | — |
Reliability
Provider status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
Grok 4 Fast Reasoning vs …
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Solar Open 2 250B-A15B vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
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