Gemini 3 Flash vs Gemini 3 Pro Preview

Detailed comparison between Gemini 3 Flash and Gemini 3 Pro Preview for RAG applications. See which LLM best meets your accuracy, performance, and cost needs. If you want to compare these models on your data, try Agentset.

Model Comparison

Gemini 3 Flash takes the lead.

Both Gemini 3 Flash and Gemini 3 Pro Preview are powerful language models designed for RAG applications. However, their performance characteristics differ in important ways.

Why Gemini 3 Flash:

  • Gemini 3 Flash has 93 higher ELO rating
  • Gemini 3 Flash delivers better overall quality (4.99 vs 4.93)
  • Gemini 3 Flash is 10.1s faster on average
  • Gemini 3 Flash has a 16.5% higher win rate

Overview

Key metrics

ELO Rating

Overall ranking quality

Gemini 3 Flash

1570

Gemini 3 Pro Preview

1477

Win Rate

Head-to-head performance

Gemini 3 Flash

56.8%

Gemini 3 Pro Preview

40.3%

Quality Score

Overall quality metric

Gemini 3 Flash

4.99

Gemini 3 Pro Preview

4.93

Average Latency

Response time

Gemini 3 Flash

7802ms

Gemini 3 Pro Preview

17903ms

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Visual Performance Analysis

Performance

ELO Rating Comparison

Win/Loss/Tie Breakdown

Quality Across Datasets (Overall Score)

Latency Distribution (ms)

Breakdown

How the models stack up

MetricGemini 3 FlashGemini 3 Pro PreviewDescription
Overall Performance
ELO Rating
1570
1477
Overall ranking quality based on pairwise comparisons
Win Rate
56.8%
40.3%
Percentage of comparisons won against other models
Quality Score
4.99
4.93
Average quality across all RAG metrics
Pricing & Context
Input Price per 1M
$0.50
$2.00
Cost per million input tokens
Output Price per 1M
$3.00
$12.00
Cost per million output tokens
Context Window
1049K
1049K
Maximum context window size
Release Date
2025-12-17
2025-11-18
Model release date
Performance Metrics
Avg Latency
7.8s
17.9s
Average response time across all datasets

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for (const result of results) {
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}

Dataset Performance

By benchmark

Comprehensive comparison of RAG quality metrics (correctness, faithfulness, grounding, relevance, completeness) and latency for each benchmark dataset.

MSMARCO

MetricGemini 3 FlashGemini 3 Pro PreviewDescription
Quality Metrics
Correctness
5.00
5.00
Factual accuracy of responses
Faithfulness
5.00
5.00
Adherence to source material
Grounding
5.00
5.00
Citations and context usage
Relevance
5.00
5.00
Query alignment and focus
Completeness
5.00
5.00
Coverage of all aspects
Overall
5.00
5.00
Average across all metrics
Latency Metrics
Mean
6852ms
13990ms
Average response time
Min3389ms7461msFastest response time
Max9837ms26343msSlowest response time

PG

MetricGemini 3 FlashGemini 3 Pro PreviewDescription
Quality Metrics
Correctness
5.00
4.89
Factual accuracy of responses
Faithfulness
5.00
4.89
Adherence to source material
Grounding
5.00
4.89
Citations and context usage
Relevance
5.00
5.00
Query alignment and focus
Completeness
5.00
4.72
Coverage of all aspects
Overall
5.00
4.88
Average across all metrics
Latency Metrics
Mean
9444ms
25137ms
Average response time
Min5346ms13317msFastest response time
Max12549ms62299msSlowest response time

SciFact

MetricGemini 3 FlashGemini 3 Pro PreviewDescription
Quality Metrics
Correctness
5.00
4.91
Factual accuracy of responses
Faithfulness
5.00
5.00
Adherence to source material
Grounding
5.00
5.00
Citations and context usage
Relevance
4.91
4.91
Query alignment and focus
Completeness
4.91
4.73
Coverage of all aspects
Overall
4.96
4.91
Average across all metrics
Latency Metrics
Mean
7110ms
14583ms
Average response time
Min3784ms10135msFastest response time
Max18224ms21489msSlowest response time

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