Noometry

Model comparison

Gemini 3.5 Flash vs Mercury 2.5

Gemini 3.5 Flash has enough public results to be ranked (#29); Mercury 2.5 does not yet, so treat this comparison as directional.

Last verified . 2 shared benchmarks.

Gemini 3.5 Flash Google

54.1

Rank #29 Confirmed

Mercury 2.5 Inception

30.2

Unranked Sparse

Summary

  • They share 2 benchmarks with published results for both. Gemini 3.5 Flash scores higher in 1 category and Mercury 2.5 in 0 categories; one gap is clear of the uncertainty.
  • The widest gap is in math, where Gemini 3.5 Flash leads 60.5 to 22.4.
  • The biggest single-benchmark swing is ProofBench: 31% for Gemini 3.5 Flash and 3% for Mercury 2.5.
  • Mercury 2.5 is cheaper at $0.04 / $0.15 per million input/output tokens, against $1.50 / $9 for Gemini 3.5 Flash.
  • Gemini 3.5 Flash accepts more context: 1.05M tokens versus 260K.

Side by side

Gemini 3.5 FlashMercury 2.5
ProviderGoogleInception
Noometry Index54.130.2
Released2026-05-192026-09-08
WeightsProprietaryProprietary
Context window1.05M260K
Max output66K66K
Input $ / M tokens$1.50$0.04
Output $ / M tokens$9$0.15
Results tracked542

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Category by category

Coding Not comparable

Gemini 3.5 Flash: 49.1 (#46), Mercury 2.5: —

BenchmarkGemini 3.5 FlashMercury 2.5
ALE-Bench911.02301.65
SWE-bench Verified79.3%—
DeepSWE37.4%—
LMArena WebDev1499—
SciCode53.1%—
WeirdML62.6%—
LMArena Coding1492—

Agentic & Tool Use Not comparable

Gemini 3.5 Flash: 24.8 (#107), Mercury 2.5: —

BenchmarkGemini 3.5 FlashMercury 2.5
APEX-Agents27.5%—
GBAEval6.7%—
GDP.pdf14%—
Vending-Bench 25,396—

Reasoning Not comparable

Gemini 3.5 Flash: 62.7 (#16), Mercury 2.5: —

BenchmarkGemini 3.5 FlashMercury 2.5
ARC-AGI-272.1%—
SimpleBench76.7%—
NYT Connections (extended)92.6%—
ARC-AGI-192.5%—
CritPt13.1%—
Chess Puzzles50%—
EnigmaEval25.4%—
EBR-Bench4.8%—
LMArena Hard Prompts1488—
Mystery Game Puzzles32%—
DTBench94.7%—
LMCA47.1%—
Surface Evolver Bench58.1%—
Epoch Capabilities Index154.55—
ForecastBench59—

Math Gemini 3.5 Flash leads

Gemini 3.5 Flash: 60.5 (#30), Mercury 2.5: 22.4

BenchmarkGemini 3.5 FlashMercury 2.5
ProofBench31%3%
FrontierMath (Tiers 1-3)62.8%—
FrontierMath Tier 426.8%—
MathArena Final-Answer Competitions76.3%—
OTIS Mock AIME 2024-202595.6%—
LMArena Math1502—
FrontierMath (Feb 2025 set)39%—
FrontierMath Tier 4 (v1)14.6%—

Knowledge Not comparable

Gemini 3.5 Flash: 66.3 (#10), Mercury 2.5: —

BenchmarkGemini 3.5 FlashMercury 2.5
GPQA Diamond92.8%—
SimpleQA Verified66.2%—
LMArena Expert1493—

Multimodal Not comparable

Gemini 3.5 Flash: 45.7 (#13), Mercury 2.5: —

BenchmarkGemini 3.5 FlashMercury 2.5
LMArena Vision1311—
Blueprint-Bench 233.6%—
LMArena Document1463—

Multilingual Not comparable

Gemini 3.5 Flash: 57.1 (#12), Mercury 2.5: —

BenchmarkGemini 3.5 FlashMercury 2.5
LMArena Non-English1475—
LMArena Chinese1525—
LMArena French1490—
LMArena German1500—
LMArena Japanese1481—
LMArena Korean1453—
LMArena Russian1491—
LMArena Spanish1478—

Instruction Following Not comparable

Gemini 3.5 Flash: 77.2 (#29), Mercury 2.5: —

BenchmarkGemini 3.5 FlashMercury 2.5
LMArena Instruction Following1466—

Long Context Not comparable

Gemini 3.5 Flash: 45.3 (#39), Mercury 2.5: —

BenchmarkGemini 3.5 FlashMercury 2.5
LMArena Longer Query1481—

Writing & Preference Not comparable

Gemini 3.5 Flash: 65.5 (#46), Mercury 2.5: —

BenchmarkGemini 3.5 FlashMercury 2.5
LMArena Text1481—
LMArena Creative Writing1467—
EQ-Bench 41087—
LMArena Multi-Turn1482—

Frequently asked questions

Is Gemini 3.5 Flash better than Mercury 2.5?

Gemini 3.5 Flash has enough public results to be ranked (#29); Mercury 2.5 does not yet, so treat this comparison as directional.

Which is cheaper, Gemini 3.5 Flash or Mercury 2.5?

Mercury 2.5 is cheaper. It lists at $0.04 per million input tokens and $0.15 per million output tokens; Gemini 3.5 Flash lists at $1.50 and $9.

Which has the bigger context window?

Gemini 3.5 Flash does, with 1.05M tokens against 260K.

How many benchmarks do Gemini 3.5 Flash and Mercury 2.5 share?

2 benchmarks have published results for both models. Gemini 3.5 Flash has 54 scored results on Noometry and Mercury 2.5 has 2.

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