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Model comparison

GPT-5.5 Pro vs Grok 3 [Beta]

Data verified

Head-to-head evidence from 2 shared benchmark results across 1 category. Overall scores shown here use the public BenchAlign v5 ranking lane.

63.69/100
Margin
23.3pts
← winning
40.43/100
1 category wins0 category wins

Public leaderboard positions: GPT-5.5 Pro #38 (Estimated); Grok 3 [Beta] #171 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. GPT-5.5 Pro and Grok 3 [Beta] share 2 comparable benchmark results. 1 of 8 categories are comparable. 5 results are unique to GPT-5.5 Pro; 0 to Grok 3 [Beta].

Updated July 22, 2026
Shared results
2
GPT-5.5 Pro only
5
Grok 3 [Beta] only
0
Comparable categories
1 / 8

Pick GPT-5.5 Pro if you want the stronger benchmark profile. Grok 3 [Beta] 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 2 shared benchmark results across 1 evidence category; 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 40.43. 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 2.8. The single biggest benchmark swing on the page is FrontierMath v2 (Tiers 1-3), 51.000% to 3.793%.

GPT-5.5 Pro is the reasoning model in the pair, while Grok 3 [Beta] 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 3 [Beta].

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 scores and score margins for GPT-5.5 Pro and Grok 3 [Beta]
CategoryGPT-5.5 ProΔGrok 3 [Beta]
MathGPT-5.5 Pro48.1Margin 45.3Grok 3 [Beta]2.8
AgenticGPT-5.5 Pro90.1MarginNo overlapGrok 3 [Beta]Not measured
KnowledgeGPT-5.5 Pro57.2MarginNo overlapGrok 3 [Beta]Not measured

Decisive benchmark drivers

The largest measured benchmark gaps in this matchup, with exact reported values.

More
A · GPT-5.5 ProB · Grok 3 [Beta]
  1. FrontierMath v2 (Tiers 1-3)

    Math
    Source ↗
    A 51.000%B 3.793%
    Winner: GPT-5.5 ProΔ 47.2
    FrontierMath v2 (Tiers 1-3): GPT-5.5 Pro scored 51.000%; Grok 3 [Beta] scored 3.793%. GPT-5.5 Pro wins this benchmark.
  2. FrontierMath v2 (Tier 4)

    Math
    Source ↗
    A 39.600%B 0.000%
    Winner: GPT-5.5 ProΔ 39.6
    FrontierMath v2 (Tier 4): GPT-5.5 Pro scored 39.600%; Grok 3 [Beta] scored 0.000%. GPT-5.5 Pro wins this benchmark.

Operational comparison

Runtime and commercial metrics are compared only when both models have a complete sourced value.

MetricGPT-5.5 ProGrok 3 [Beta]Comparison
Input / output priceUSD per 1M tokensGPT-5.5 Pro$30 input / $180 outputGrok 3 [Beta]Not availableA complete price comparison is not available.
Generation speedtokens per secondGPT-5.5 ProNot availableGrok 3 [Beta]Not availableA complete speed comparison is not available.
First-answer latencyseconds to first tokenGPT-5.5 ProNot availableGrok 3 [Beta]Not availableA complete latency comparison is not available.
Context windowmaximum listed tokensGPT-5.5 Pro1MGrok 3 [Beta]128KGPT-5.5 Pro lists the larger context window.

Benchmark Deep Dive

Agentic
BenchmarkGPT-5.5 ProGrok 3 [Beta]Result
BrowseCompSource 90.1%Not comparable
Reasoning
BenchmarkGPT-5.5 ProGrok 3 [Beta]Result
CritPtSource 30.6%Not comparable
Knowledge
BenchmarkGPT-5.5 ProGrok 3 [Beta]Result
HLESource 57.2%Not comparable
HLE w/o toolsSource 43.1%Not comparable
MathGPT-5.5 Pro wins
BenchmarkGPT-5.5 ProGrok 3 [Beta]Result
FrontierMath (legacy)Source 52.4%Not comparable
FrontierMath v2 (Tiers 1-3)Source 51.000%3.793%GPT-5.5 Pro leads
FrontierMath v2 (Tier 4)Source 39.600%0.000%GPT-5.5 Pro leads
Frequently Asked Questions (2)

Which is better, GPT-5.5 Pro or Grok 3 [Beta]?

GPT-5.5 Pro is ahead on BenchLM's BenchAlign leaderboard, 63.69 to 40.43. The biggest single separator in this matchup is FrontierMath v2 (Tiers 1-3), where the scores are 51.000% and 3.793%.

Which is better for math, GPT-5.5 Pro or Grok 3 [Beta]?

GPT-5.5 Pro has the edge for math in this comparison, averaging 48.1 versus 2.8. Inside this category, FrontierMath v2 (Tiers 1-3) is the benchmark that creates the most daylight between them.

Related Comparisons

Last updated: July 22, 2026

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