Compare / head-to-head
Grok 4 Fast ReasoningvsKimi K2.6
Kimi K2.6 leads 1 of 1 shared benchmark. 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 – 1
Kimi K2.6 leads
Cheaper per token
—
list price, input + output
Larger context
Grok 4 Fast Reasoning
2M tokens
Provider uptime (30d)
— · 100%
xAI · Moonshot AI
Grok 4 Fast Reasoning
xAI · released 2025-09-19
text
Kimi K2.6
Moonshot AI · released 2026-04-20
textvision
- Context
- 256K
- Max out
- —
- Input /1M
- —
- Output /1M
- —
- Cached /1M
- —
- Scores
- 14 · 8 core
Quality
Benchmark matrix
1 shared · 11 only Grok 4 Fast Reasoning · 13 only Kimi K2.6| Benchmark | Grok 4 Fast Reasoning | Kimi K2.6 | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 1 | ||||
| GPQA Diamond | 85.7% ↗ | 90.8% ↗epoch | -5.1 pt | Kimi K2.6 |
| Only Grok 4 Fast Reasoning reports · 11 | ||||
| AIME 2025 | 92% ↗ | not reported | — | — |
| 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 Kimi K2.6 reports · 13 | ||||
| AIME 2026 | not reported | 95.8% ↗matharena ⚠ | — | — |
| LMArena Elo | not reported | 1454.9 ↗ | — | — |
| FrontierMath Tier 4 v2 (Epoch AI run) | not reported | 25.6% ↗epoch | — | — |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | not reported | 57.2% ↗epoch | — | — |
| Kimi Claw 24/7 Bench | not reported | 42.9% ↗ | — | — |
| Kimi Code Bench v2 | not reported | 50.9% ↗ | — | — |
| MCP-Atlas | not reported | 69.4% ↗ | — | — |
| MCPMark-Verified | not reported | 72.8% ↗ | — | — |
| MLS-Bench-Lite | not reported | 26.7% ↗ | — | — |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | not reported | 96.1% ↗epoch | — | — |
| ProgramBench | not reported | 48.3% ↗ | — | — |
| SimpleQA Verified | not reported | 34.9% ↗epoch | — | — |
| SWE-bench Verified (Epoch AI run) | not reported | 76.7% ↗epoch | — | — |
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 Kimi K2.6 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 | Kimi K2.6 | Edge |
|---|---|---|---|
| Context window | 2M tokens | 256K 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 · vision | Kimi K2.6 |
| Released | 2025-09-19 | 2026-04-20 | — |
| Cited benchmark scores | 12 | 14 | — |
Reliability
Provider status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
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Kimi K2.6 vs …
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Which one wins on your data?
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