Compare / head-to-head
Grok 4 Fast ReasoningvsPhi-4 Reasoning
Grok 4 Fast Reasoning 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
2 – 0
Grok 4 Fast Reasoning leads
Cheaper per token
—
list price, input + output
Larger context
Grok 4 Fast Reasoning
2M tokens
Provider uptime (30d)
— · —
xAI · Microsoft
Grok 4 Fast Reasoning
xAI · released 2025-09-19
text
Phi-4 Reasoning
Microsoft · released 2025-04-30
text
- Context
- 33K
- Max out
- 33K
- Input /1M
- —
- Output /1M
- —
- Cached /1M
- —
- Scores
- 4 · 4 core
Quality
Benchmark matrix
2 shared · 10 only Grok 4 Fast Reasoning · 2 only Phi-4 Reasoning| Benchmark | Grok 4 Fast Reasoning | Phi-4 Reasoning | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 2 | ||||
| GPQA Diamond | 85.7% ↗ | 65.8% ↗ | +19.9 pt | Grok 4 Fast Reasoning |
| AIME 2025 | 92% ↗ | 62.9% ↗ | +29.1 pt | Grok 4 Fast Reasoning |
| Only Grok 4 Fast Reasoning reports · 10 | ||||
| Humanity's Last Exam (no tools) | 20% ↗ | 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 Phi-4 Reasoning reports · 2 | ||||
| MMLU-Pro | not reported | 74.3% ↗ | — | — |
| HumanEval+ | not reported | 92.9% ↗ | — | — |
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 Phi-4 Reasoning 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 | Phi-4 Reasoning | Edge |
|---|---|---|---|
| Context window | 2M tokens | 33K tokens | Grok 4 Fast Reasoning |
| Max output | — | 33K tokens | — |
| 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 | 2025-04-30 | — |
| Cited benchmark scores | 12 | 4 | — |
Reliability
Provider status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
Grok 4 Fast Reasoning vs …
Models sharing the most benchmarksMore matchups
Phi-4 Reasoning vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
Public benchmarks are a starting point. Run Grok 4 Fast Reasoning and Phi-4 Reasoning on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.