Compare / head-to-head
GPT-5.1vsGrok 4.5
Grok 4.5 leads 4 of 4 shared benchmarks. Grok 4.5 is 1.4x cheaper per token. Grok 4.5 has the larger context window (500K tokens).
Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.
Shared benchmarks
0 – 4
Grok 4.5 leads
Cheaper per token
Grok 4.5
1.4x cheaper, input + output
Larger context
Grok 4.5
500K tokens
Provider uptime (30d)
95.122% · —
OpenAI · xAI
GPT-5.1
OpenAI · released 2025-11-13
textvision
Quality
Benchmark matrix
4 shared · 2 only GPT-5.1 · 2 only Grok 4.5| Benchmark | GPT-5.1 | Grok 4.5 | Δ | Edge |
|---|---|---|---|---|
| Reported by both · 4 | ||||
| GPQA Diamond | 87.6% ↗epoch | 93.4% ↗epoch | -5.8 pt | Grok 4.5 |
| LMArena Elo | 1422.6 ↗ | 1450.1 ↗ | -27.5 | Grok 4.5 |
| OTIS Mock AIME 2024-2025 (Epoch AI run) | 88.6% ↗epoch | 97.8% ↗epoch | -9.2 pt | Grok 4.5 |
| SimpleQA Verified | 48% ↗epoch | 48.3% ↗epoch | -0.3 pt | Grok 4.5 |
| Only GPT-5.1 reports · 2 | ||||
| AIME 2025 | 94.2% ↗matharena ⚠ | not reported | — | — |
| SWE-bench Verified (Epoch AI run) | 68% ↗epoch | not reported | — | — |
| Only Grok 4.5 reports · 2 | ||||
| FrontierMath Tier 4 v2 (Epoch AI run) | not reported | 24.4% ↗epoch | — | — |
| FrontierMath Tiers 1-3 v2 (Epoch AI run) | not reported | 57.2% ↗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 GPT-5.1 minus Grok 4.5 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 | GPT-5.1 | Grok 4.5 | Edge |
|---|---|---|---|
| Context window | 400K tokens | 500K tokens | Grok 4.5 |
| Max output | 128K tokens | — | — |
| Input price / 1M | $1.25 ↗ | $2 ↗ | GPT-5.1 |
| Output price / 1M | $10 ↗ | $6 ↗ | Grok 4.5 |
| Cached input / 1M | $0.125 ↗ | $0.3 ↗ | GPT-5.1 |
| Input + output / 1M Lower is cheaper. List prices; batch, tool and regional fees excluded. | $11.25 | $8 | Grok 4.5 |
| Modalities | text · vision | text · vision | Tie |
| Released | 2025-11-13 | 2026-07-08 | — |
| Cited benchmark scores | 6 | 6 | — |
Reliability
Provider status
Last 60 days · refreshed daily on this page · live on /statusMore matchups
GPT-5.1 vs …
Models sharing the most benchmarksMore matchups
Grok 4.5 vs …
Models sharing the most benchmarksBuilt by Respan
Which one wins on your data?
Public benchmarks are a starting point. Run GPT-5.1 and Grok 4.5 on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.