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Model comparison

Gemma 4 26B A4B vs GPT-5.5 Pro

Data verified

Head-to-head evidence from 3 shared benchmark results across 2 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

57.96/100
Margin
5.7pts
winning →
63.69/100
0 category wins1 category wins

Public leaderboard positions: Gemma 4 26B A4B #67 (Supported); GPT-5.5 Pro #38 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Gemma 4 26B A4B and GPT-5.5 Pro share 3 comparable benchmark results. 1 of 8 categories are comparable. 17 results are unique to Gemma 4 26B A4B; 4 to GPT-5.5 Pro.

Updated July 22, 2026
Shared results
3
Gemma 4 26B A4B only
17
GPT-5.5 Pro only
4
Comparable categories
1 / 8

Pick GPT-5.5 Pro if you want the stronger benchmark profile. Gemma 4 26B A4B only becomes the better choice if you want the cheaper token bill.

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 57.96. 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 knowledge, where it averages 57.2 against 43.4. The single biggest benchmark swing on the page is HLE, 17.2% to 57.2%.

GPT-5.5 Pro is also the more expensive model on tokens at $30.00 input / $180.00 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for Gemma 4 26B A4B. That is roughly Infinityx on output cost alone. GPT-5.5 Pro gives you the larger context window at 1M, compared with 256K for Gemma 4 26B A4B.

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 Gemma 4 26B A4B and GPT-5.5 Pro
CategoryGemma 4 26B A4BΔGPT-5.5 Pro
KnowledgeGemma 4 26B A4B43.4Margin 13.8GPT-5.5 Pro57.2
AgenticGemma 4 26B A4BNot measuredMarginNo overlapGPT-5.5 Pro90.1
MathGemma 4 26B A4BNot measuredMarginNo overlapGPT-5.5 Pro48.1
MultimodalGemma 4 26B A4B73.8MarginNo overlapGPT-5.5 ProNot measured

Decisive benchmark drivers

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

More
A · Gemma 4 26B A4BB · GPT-5.5 Pro
  1. HLE

    Knowledge
    Source ↗
    A 17.2%B 57.2%
    Winner: GPT-5.5 ProΔ 40
    HLE: Gemma 4 26B A4B scored 17.2%; GPT-5.5 Pro scored 57.2%. GPT-5.5 Pro wins this benchmark.

Operational comparison

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

MetricGemma 4 26B A4BGPT-5.5 ProComparison
Input / output priceUSD per 1M tokensGemma 4 26B A4B$0 input / $0 outputGPT-5.5 Pro$30 input / $180 outputGemma 4 26B A4B has the lower combined listed price.
Generation speedtokens per secondGemma 4 26B A4BNot availableGPT-5.5 ProNot availableA complete speed comparison is not available.
First-answer latencyseconds to first tokenGemma 4 26B A4BNot availableGPT-5.5 ProNot availableA complete latency comparison is not available.
Context windowmaximum listed tokensGemma 4 26B A4B256KGPT-5.5 Pro1MGPT-5.5 Pro lists the larger context window.

Benchmark Deep Dive

Agentic
BenchmarkGemma 4 26B A4BGPT-5.5 ProResult
AA Agentic IndexSource 11.0%Not comparable
τ²-bench resultsSource 43.6%Not comparable
GDPval-AASource 13.1%Not comparable
GDPval-AASource 761Not comparable
BrowseCompSource 90.1%Not comparable
Coding
BenchmarkGemma 4 26B A4BGPT-5.5 ProResult
AA Coding IndexSource 39.3%Not comparable
AA-SciCodeSource 40.0%Not comparable
Reasoning
BenchmarkGemma 4 26B A4BGPT-5.5 ProResult
AA-LCRSource 55.7%Not comparable
CritPtSource 0.0%30.6%GPT-5.5 Pro leads
KnowledgeGPT-5.5 Pro wins
BenchmarkGemma 4 26B A4BGPT-5.5 ProResult
MMLU-ProSource 82.6%Not comparable
HLESource 17.2%57.2%GPT-5.5 Pro leads
HLE w/o toolsSource 8.7%43.1%GPT-5.5 Pro leads
Artificial Analysis Intelligence IndexSource 25.7%Not comparable
AA-GPQA DiamondSource 79.2%Not comparable
AA-HLESource 18.3%Not comparable
AA-Omniscience IndexSource -48.1%Not comparable
AA-Omniscience AccuracySource 18.2%Not comparable
AA-Omniscience Hallucination RateSource 80.9%Not comparable
Math
BenchmarkGemma 4 26B A4BGPT-5.5 ProResult
FrontierMath (legacy)Source 52.4%Not comparable
FrontierMath v2 (Tiers 1-3)Source 51.000%Not comparable
FrontierMath v2 (Tier 4)Source 39.600%Not comparable
Multimodal
BenchmarkGemma 4 26B A4BGPT-5.5 ProResult
MMMU-ProSource 73.8%Not comparable
AA-MMMU-ProSource 69.2%Not comparable
Inst. Following
BenchmarkGemma 4 26B A4BGPT-5.5 ProResult
AA-IFBenchSource 72.4%Not comparable
Frequently Asked Questions (2)

Which is better, Gemma 4 26B A4B or GPT-5.5 Pro?

GPT-5.5 Pro is ahead on BenchLM's BenchAlign leaderboard, 63.69 to 57.96. The biggest single separator in this matchup is HLE, where the scores are 17.2% and 57.2%.

Which is better for knowledge tasks, Gemma 4 26B A4B or GPT-5.5 Pro?

GPT-5.5 Pro has the edge for knowledge tasks in this comparison, averaging 57.2 versus 43.4. Inside this category, HLE is the benchmark that creates the most daylight between them.

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Last updated: July 22, 2026

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