Noometry

Model comparison

Gemini 2.5 Pro vs gpt-oss-20b

Gemini 2.5 Pro is the stronger model overall, scoring 45.0 to 32.5 on the Noometry Index. gpt-oss-20b costs 95× less per token, which makes it the better buy when Gemini 2.5 Pro's lead doesn't matter for your workload.

Last verified . 34 shared benchmarks.

Gemini 2.5 Pro Google

45.0

Rank #75 Confirmed

gpt-oss-20b OpenAI

32.5

Rank #255 Confirmed

Summary

  • They share 34 benchmarks with published results for both. Gemini 2.5 Pro scores higher in 8 categories and gpt-oss-20b in 1 category; 9 gaps are clear of the uncertainty.
  • The widest gap is in writing & preference, where Gemini 2.5 Pro leads 63.7 to 35.5.
  • The biggest single-benchmark swing is Terminal-Bench: 32.6% for Gemini 2.5 Pro and 3.4% for gpt-oss-20b.
  • gpt-oss-20b is cheaper at $0.018 / $0.09 per million input/output tokens, against $1.25 / $10 for Gemini 2.5 Pro.
  • Gemini 2.5 Pro accepts more context: 1.05M tokens versus 131K.
  • gpt-oss-20b has downloadable open weights; the other is API-only.

Side by side

Gemini 2.5 Progpt-oss-20b
ProviderGoogleOpenAI
Noometry Index45.032.5
Released2025-03-252025-08-05
WeightsProprietaryOpen
Context window1.05M131K
Max output66K16K
Input $ / M tokens$1.25$0.018
Output $ / M tokens$10$0.09
Results tracked7834

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Category by category

Coding Gemini 2.5 Pro leads

Gemini 2.5 Pro: 42.4 (#101), gpt-oss-20b: 37.6 (#192)

BenchmarkGemini 2.5 Progpt-oss-20b
SciCode42.8%34.4%
WeirdML54%40.9%
LMArena Coding14521306
ALE-Bench785.52566.05
SWE-bench Verified57.6%—
SWE-bench Verified (bash only)53.6%—
Aider Polyglot83.1%—
LMArena WebDev1227—
GSO3.9%—
LiveBench Coding85.9%—
CadEval64%—
AlgoTune1.51—

Agentic & Tool Use Gemini 2.5 Pro leads

Gemini 2.5 Pro: 29.2 (#88), gpt-oss-20b: 9.3 (#154)

BenchmarkGemini 2.5 Progpt-oss-20b
Terminal-Bench32.6%3.4%
GDPval23.3%—
Remote Labor Index0.8%—
TheAgentCompany30.3%—
τ²-bench Banking13.7%—
DeepResearch Bench42.8%—
BALROG43.3%—
LMArena Search1142—
METR Time Horizons55.4%—
Vending-Bench 2573.64—

Reasoning Gemini 2.5 Pro leads

Gemini 2.5 Pro: 28.8 (#99), gpt-oss-20b: 19.3 (#261)

BenchmarkGemini 2.5 Progpt-oss-20b
Kagi LLM Benchmark70.3%53.2%
CritPt2%1.4%
Chess Puzzles20%4%
LMArena Hard Prompts14551274
DTBench82.4%68%
LMCA34.8%14.5%
Epoch Capabilities Index145.32137.82
ARC-AGI-24.9%—
SimpleBench62.4%—
ARC-AGI-141%—
EnigmaEval5.6%—
LiveBench Reasoning89.8%—
LiveBench Data Analysis79.9%—
ForecastBench61.3—
LiveBench82.3%—

Math gpt-oss-20b leads

Gemini 2.5 Pro: 32.5 (#213), gpt-oss-20b: 39.4 (#103)

BenchmarkGemini 2.5 Progpt-oss-20b
OTIS Mock AIME 2024-202584.7%65.3%
Omni-MATH41.6%56.5%
LMArena Math14501317
FrontierMath (Tiers 1-3)24.6%—
FrontierMath Tier 40%—
LiveBench Math90.2%—
MATH Level 595.9%—
FrontierMath (Feb 2025 set)14.1%—
FrontierMath Tier 4 (v1)4.2%—

Knowledge Gemini 2.5 Pro leads

Gemini 2.5 Pro: 56.0 (#46), gpt-oss-20b: 34.6 (#195)

BenchmarkGemini 2.5 Progpt-oss-20b
GPQA Diamond85.3%60.8%
MMLU-Pro86.3%74%
GPQA (HELM)74.9%59.4%
LMArena Expert14521258
Humanity's Last Exam21.6%—
Confabulations10.6%—
Vectara Hallucination Rate7%—

Multimodal Not comparable

Gemini 2.5 Pro: 45.2 (#18), gpt-oss-20b: —

BenchmarkGemini 2.5 Progpt-oss-20b
LMArena Vision1263—
GeoBench86%—
VPCT48%—
LMArena Document1421—
SpatialViz-Bench44.7%—

Multilingual Gemini 2.5 Pro leads

Gemini 2.5 Pro: 55.3 (#31), gpt-oss-20b: 42.2 (#197)

BenchmarkGemini 2.5 Progpt-oss-20b
LMArena Non-English14511268
LMArena Chinese15071314
LMArena German14871255
LMArena Japanese14611244
LMArena Korean14341236
LMArena Russian14611278
LMArena Spanish14731267
LMArena French1472—

Instruction Following Gemini 2.5 Pro leads

Gemini 2.5 Pro: 75.0 (#75), gpt-oss-20b: 61.8 (#240)

BenchmarkGemini 2.5 Progpt-oss-20b
IFEval84%73.2%
LMArena Instruction Following14371236
LiveBench Instruction Following80.6%—

Long Context Gemini 2.5 Pro leads

Gemini 2.5 Pro: 59.8 (#5), gpt-oss-20b: 37.9 (#209)

BenchmarkGemini 2.5 Progpt-oss-20b
LMArena Longer Query14491250
Fiction.LiveBench91.7%—

Writing & Preference Gemini 2.5 Pro leads

Gemini 2.5 Pro: 63.7 (#62), gpt-oss-20b: 35.5 (#265)

BenchmarkGemini 2.5 Progpt-oss-20b
LMArena Text14581287
LMArena Creative Writing14541201
EQ-Bench Creative Writing1421666
WildBench85.7%73.7%
LMArena Multi-Turn14531268
Short-Story Creative Writing83.8%—
LiveBench Language67.8%—

Frequently asked questions

Is Gemini 2.5 Pro better than gpt-oss-20b?

Gemini 2.5 Pro is the stronger model overall, scoring 45.0 to 32.5 on the Noometry Index. gpt-oss-20b costs 95× less per token, which makes it the better buy when Gemini 2.5 Pro's lead doesn't matter for your workload.

Which is cheaper, Gemini 2.5 Pro or gpt-oss-20b?

gpt-oss-20b is cheaper. It lists at $0.018 per million input tokens and $0.09 per million output tokens; Gemini 2.5 Pro lists at $1.25 and $10.

Is Gemini 2.5 Pro or gpt-oss-20b better for coding?

Gemini 2.5 Pro scores higher on coding benchmarks: 42.4 versus 37.6 in the Noometry coding category.

Which has the bigger context window?

Gemini 2.5 Pro does, with 1.05M tokens against 131K.

How many benchmarks do Gemini 2.5 Pro and gpt-oss-20b share?

34 benchmarks have published results for both models. Gemini 2.5 Pro has 78 scored results on Noometry and gpt-oss-20b has 34.

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