Skip to main content

Model comparison

Gemma 4 31B vs GPT-5.5

Data verified

Head-to-head evidence from 26 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

61.08/100
Margin
12.4pts
winning →
OpenAI
73.51/100
1 category wins2 category wins

Public leaderboard positions: Gemma 4 31B #43 (Supported); GPT-5.5 #9 (Estimated). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. Gemma 4 31B and GPT-5.5 share 26 comparable benchmark results. 3 of 8 categories are comparable. 3 results are unique to Gemma 4 31B; 31 to GPT-5.5.

Updated July 22, 2026
Shared results
26
Gemma 4 31B only
3
GPT-5.5 only
31
Comparable categories
3 / 8

Pick GPT-5.5 if you want the stronger benchmark profile. Gemma 4 31B only becomes the better choice if multimodal & grounded is the priority or you want the cheaper token bill.

Confidence note. This is a partial-evidence comparison with 26 shared benchmark results across 6 evidence categories; 3 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 is clearly ahead on the BenchAlign aggregate, 73.51 to 61.08. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.5's sharpest advantage is in coding, where it averages 58.6 against 41.6. The single biggest benchmark swing on the page is HLE, 26.5% to 52.2%. Gemma 4 31B does hit back in multimodal & grounded, so the answer changes if that is the part of the workload you care about most.

GPT-5.5 is also the more expensive model on tokens at $5.00 input / $30.00 output per 1M tokens, versus $0.00 input / $0.00 output per 1M tokens for Gemma 4 31B. That is roughly Infinityx on output cost alone. GPT-5.5 gives you the larger context window at 1M, compared with 256K for Gemma 4 31B.

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 31B and GPT-5.5
CategoryGemma 4 31BΔGPT-5.5
CodingGemma 4 31B41.6Margin 17.0GPT-5.558.6
MultimodalGemma 4 31B76.9Margin 6.5GPT-5.570.4
KnowledgeGemma 4 31B52.9Margin 4.9GPT-5.557.8
AgenticGemma 4 31BNot measuredMarginNo overlapGPT-5.581.6
ReasoningGemma 4 31BNot measuredMarginNo overlapGPT-5.585.0
MathGemma 4 31BNot measuredMarginNo overlapGPT-5.547.6

Decisive benchmark drivers

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

More
A · Gemma 4 31BB · GPT-5.5
  1. HLE

    Knowledge
    Source ↗
    A 26.5%B 52.2%
    Winner: GPT-5.5Δ 25.7
    HLE: Gemma 4 31B scored 26.5%; GPT-5.5 scored 52.2%. GPT-5.5 wins this benchmark.
  2. GPQA

    Knowledge
    Source ↗
    A 84.3%B 93.6%
    Winner: GPT-5.5Δ 9.3
    GPQA: Gemma 4 31B scored 84.3%; GPT-5.5 scored 93.6%. GPT-5.5 wins this benchmark.
  3. MMMU-Pro

    Multimodal
    Source ↗
    A 76.9%B 81.2%
    Winner: GPT-5.5Δ 4.3
    MMMU-Pro: Gemma 4 31B scored 76.9%; GPT-5.5 scored 81.2%. GPT-5.5 wins this benchmark.

Operational comparison

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

MetricGemma 4 31BGPT-5.5Comparison
Input / output priceUSD per 1M tokensGemma 4 31B$0 input / $0 outputGPT-5.5$5 input / $30 outputGemma 4 31B has the lower combined listed price.
Generation speedtokens per secondGemma 4 31BNot availableGPT-5.5Not availableA complete speed comparison is not available.
First-answer latencyseconds to first tokenGemma 4 31BNot availableGPT-5.5Not availableA complete latency comparison is not available.
Context windowmaximum listed tokensGemma 4 31B256KGPT-5.51MGPT-5.5 lists the larger context window.

Benchmark Deep Dive

Agentic
BenchmarkGemma 4 31BGPT-5.5Result
AA Agentic IndexSource 14.4%44.9%GPT-5.5 leads
τ²-bench resultsSource 59.9%93.9%GPT-5.5 leads
GDPval-AASource 15.2%49.5%GPT-5.5 leads
GDPval-AASource 8041490GPT-5.5 leads
Gert LabsSource 35.26%72.93%GPT-5.5 leads
AA EnterpriseOps-GymSource 28.3%46.6%GPT-5.5 leads
AA ITBenchSource 37.3%45.8%GPT-5.5 leads
AA Tau3 BankingSource 15.1%31.3%GPT-5.5 leads
terminalBenchHardSource 36.4%60.6%GPT-5.5 leads
Terminal-Bench 2.0Source 82%Not comparable
CyberGymSource 81.8%Not comparable
BrowseCompSource 84.4%Not comparable
OSWorld-VerifiedSource 78.7%Not comparable
MCP AtlasSource 75.3%Not comparable
ToolathlonSource 55.6%Not comparable
APEX-Agents-AASource 37.7%Not comparable
ResearchClawBenchSource 17.0%Not comparable
OSWorld 2.0Source 13.0%Not comparable
JobBenchSource 42.7%Not comparable
ExploitGymSource 13.4%Not comparable
AA BriefcaseSource 1154Not comparable
AA AutomationBenchSource 42.1%Not comparable
AA Harvey LABSource 86.3%Not comparable
aaTerminalBench21Source 84.3%Not comparable
CodingGPT-5.5 wins
BenchmarkGemma 4 31BGPT-5.5Result
SWE-RebenchSource 41.6%Not comparable
React Native EvalsSource 75.2%84.7%GPT-5.5 leads
AA Coding IndexSource 43.4%74.9%GPT-5.5 leads
AA-SciCodeSource 43.4%56.1%GPT-5.5 leads
SWE-bench ProSource 58.6%Not comparable
Terminal-Bench 2.0Source 82.0%Not comparable
Vibe Code BenchSource 69.85%Not comparable
cursorBench31Source 59.2%Not comparable
cursorBench32Source 58.4%Not comparable
FrontierCode 1.1 MainSource 43.0%Not comparable
Reasoning
BenchmarkGemma 4 31BGPT-5.5Result
AA-LCRSource 62.0%74.3%GPT-5.5 leads
CritPtSource 1.4%27.1%GPT-5.5 leads
MRCR v2 64K-128KSource 83.1%Not comparable
MRCR v2 128K-256KSource 87.5%Not comparable
ARC-AGI-2Source 85%Not comparable
KnowledgeGPT-5.5 wins
BenchmarkGemma 4 31BGPT-5.5Result
GPQASource 84.3%93.6%GPT-5.5 leads
MMLU-ProSource 85.2%Not comparable
HLESource 26.5%52.2%GPT-5.5 leads
HLE w/o toolsSource 19.5%41.4%GPT-5.5 leads
Artificial Analysis Intelligence IndexSource 29.4%54.8%GPT-5.5 leads
AA-GPQA DiamondSource 85.7%93.5%GPT-5.5 leads
AA-HLESource 22.7%44.3%GPT-5.5 leads
AA-Omniscience IndexSource -45.4%20.1%GPT-5.5 leads
AA-Omniscience AccuracySource 19.9%56.9%GPT-5.5 leads
AA-Omniscience Hallucination RateSource 81.6%85.5%Gemma 4 31B leads
AA Openness IndexSource 38.9%Not comparable
GPQA-DSource 93.6%Not comparable
Math
BenchmarkGemma 4 31BGPT-5.5Result
FrontierMath (legacy)Source 51.7%Not comparable
FrontierMath v2 (Tiers 1-3)Source 51.700%Not comparable
FrontierMath v2 (Tier 4)Source 35.400%Not comparable
MultimodalGemma 4 31B wins
BenchmarkGemma 4 31BGPT-5.5Result
MMMU-ProSource 76.9%81.2%GPT-5.5 leads
AA-MMMU-ProSource 73.4%79.9%GPT-5.5 leads
MMMU-Pro w/ PythonSource 83.2%Not comparable
OfficeQA ProSource 54.1%Not comparable
Design Arena WebsiteSource 1282Not comparable
Inst. Following
BenchmarkGemma 4 31BGPT-5.5Result
AA-IFBenchSource 75.6%75.9%GPT-5.5 leads
Frequently Asked Questions (4)

Which is better, Gemma 4 31B or GPT-5.5?

GPT-5.5 is ahead on BenchLM's BenchAlign leaderboard, 73.51 to 61.08. The biggest single separator in this matchup is HLE, where the scores are 26.5% and 52.2%.

Which is better for knowledge tasks, Gemma 4 31B or GPT-5.5?

GPT-5.5 has the edge for knowledge tasks in this comparison, averaging 57.8 versus 52.9. Inside this category, AA-Omniscience Index is the benchmark that creates the most daylight between them.

Which is better for coding, Gemma 4 31B or GPT-5.5?

GPT-5.5 has the edge for coding in this comparison, averaging 58.6 versus 41.6. Inside this category, AA Coding Index is the benchmark that creates the most daylight between them.

Which is better for multimodal and grounded tasks, Gemma 4 31B or GPT-5.5?

Gemma 4 31B has the edge for multimodal and grounded tasks in this comparison, averaging 76.9 versus 70.4. Inside this category, AA-MMMU-Pro is the benchmark that creates the most daylight between them.

Self-host vs API cost

Estimates at 50,000 req/day · 1000 tokens/req average.

Gemma 4 31B
API / mo$0
Self-host / mo$429
Break-even
GPT-5.5
API / mo$26,250
Self-host / moNot listed
Break-even
Proprietary model — self-hosting not applicable.
Model the full break-even

Related Comparisons

Last updated: July 22, 2026

Choose a model with this week’s evidence

Join 2,000+ readers for ranking moves, pricing changes, and the claims that still need proof.

One email each week. Unsubscribe anytime.