Model comparison
GPT-5.5 Pro vs Grok 4
Head-to-head evidence from 3 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.
Public leaderboard positions: GPT-5.5 Pro #38 (Estimated); Grok 4 #50 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.
Evidence parity. GPT-5.5 Pro and Grok 4 share 3 comparable benchmark results. 1 of 8 categories are comparable. 4 results are unique to GPT-5.5 Pro; 13 to Grok 4.
Updated July 22, 2026- Shared results
- 3
- GPT-5.5 Pro only
- 4
- Grok 4 only
- 13
- Comparable categories
- 1 / 8
Pick GPT-5.5 Pro if you want the stronger benchmark profile. Grok 4 only becomes the better choice if you would rather avoid the extra latency and token burn of a reasoning model.
Confidence note. This is a partial-evidence comparison with 3 shared benchmark results across 2 evidence categories; 1 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.
Why this result
GPT-5.5 Pro is clearly ahead on the BenchAlign aggregate, 63.69 to 60.42. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.
GPT-5.5 Pro's sharpest advantage is in mathematics, where it averages 48.1 against 15.3. The single biggest benchmark swing on the page is FrontierMath v2 (Tier 4), 39.600% to 2.083%.
GPT-5.5 Pro is the reasoning model in the pair, while Grok 4 is not. That usually helps on harder chain-of-thought-heavy tests, but it can also mean more latency and more token spend in real use. GPT-5.5 Pro gives you the larger context window at 1M, compared with 128K for Grok 4.
Category breakdown
Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.
| Category | GPT-5.5 Pro | Δ | Grok 4 |
|---|---|---|---|
| Math | GPT-5.5 Pro48.1 | Margin← 32.8 | Grok 415.3 |
| Agentic | GPT-5.5 Pro90.1 | MarginNo overlap | Grok 4Not measured |
| Knowledge | GPT-5.5 Pro57.2 | MarginNo overlap | Grok 4Not measured |
Decisive benchmark drivers
The largest measured benchmark gaps in this matchup, with exact reported values.
More
- Source ↗
FrontierMath v2 (Tier 4)
MathA 39.600%B 2.083%Winner: GPT-5.5 ProΔ 37.5FrontierMath v2 (Tier 4): GPT-5.5 Pro scored 39.600%; Grok 4 scored 2.083%. GPT-5.5 Pro wins this benchmark. - Source ↗
FrontierMath v2 (Tiers 1-3)
MathA 51.000%B 19.655%Winner: GPT-5.5 ProΔ 31.3FrontierMath v2 (Tiers 1-3): GPT-5.5 Pro scored 51.000%; Grok 4 scored 19.655%. GPT-5.5 Pro wins this benchmark.
Operational comparison
Runtime and commercial metrics are compared only when both models have a complete sourced value.
| Metric | GPT-5.5 Pro | Grok 4 | Comparison |
|---|---|---|---|
| Input / output priceUSD per 1M tokens | GPT-5.5 Pro$30 input / $180 output | Grok 4Not available | A complete price comparison is not available. |
| Generation speedtokens per second | GPT-5.5 ProNot available | Grok 454 tok/s | A complete speed comparison is not available. |
| First-answer latencyseconds to first token | GPT-5.5 ProNot available | Grok 415.60 s | A complete latency comparison is not available. |
| Context windowmaximum listed tokens | GPT-5.5 Pro1M | Grok 4128K | GPT-5.5 Pro lists the larger context window. |
Benchmark Deep Dive
Agentic3 benchmarks
Coding2 benchmarks
Reasoning2 benchmarks
Knowledge8 benchmarks
| Benchmark | GPT-5.5 Pro | Grok 4 | Result |
|---|---|---|---|
| HLESource | 57.2% | — | Not comparable |
| HLE w/o toolsSource | 43.1% | — | Not comparable |
| Artificial Analysis Intelligence IndexSource | — | 33.3% | Not comparable |
| AA-GPQA DiamondSource | — | 87.7% | Not comparable |
| AA-HLESource | — | 23.9% | Not comparable |
| AA-Omniscience IndexSource | — | 3.8% | Not comparable |
| AA-Omniscience AccuracySource | — | 41.4% | Not comparable |
| AA-Omniscience Hallucination RateSource | — | 64.2% | Not comparable |
MathGPT-5.5 Pro wins3 benchmarks
Multimodal1 benchmarks
| Benchmark | GPT-5.5 Pro | Grok 4 | Result |
|---|---|---|---|
| AA-MMMU-ProSource | — | 68.8% | Not comparable |
Inst. Following1 benchmarks
| Benchmark | GPT-5.5 Pro | Grok 4 | Result |
|---|---|---|---|
| AA-IFBenchSource | — | 53.7% | Not comparable |
Frequently Asked Questions (2)
Which is better, GPT-5.5 Pro or Grok 4?
GPT-5.5 Pro is ahead on BenchLM's BenchAlign leaderboard, 63.69 to 60.42. The biggest single separator in this matchup is FrontierMath v2 (Tier 4), where the scores are 39.600% and 2.083%.
Which is better for math, GPT-5.5 Pro or Grok 4?
GPT-5.5 Pro has the edge for math in this comparison, averaging 48.1 versus 15.3. Inside this category, FrontierMath v2 (Tier 4) is the benchmark that creates the most daylight between them.
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