Claude Opus 4.5 vs Gemini 2.5 Pro
Detailed comparison between Claude Opus 4.5 and Gemini 2.5 Pro for RAG applications. See which LLM best meets your accuracy, performance, and cost needs.
Model Comparison
Claude Opus 4.5 takes the lead.
Both Claude Opus 4.5 and Gemini 2.5 Pro are powerful language models designed for RAG applications. However, their performance characteristics differ in important ways.
Why Claude Opus 4.5:
- Claude Opus 4.5 has 190 higher ELO rating
- Claude Opus 4.5 is 6.9s faster on average
- Claude Opus 4.5 has a 20.6% higher win rate
Overview
Key metrics
ELO Rating
Overall ranking quality
Claude Opus 4.5
Gemini 2.5 Pro
Win Rate
Head-to-head performance
Claude Opus 4.5
Gemini 2.5 Pro
Quality Score
Overall quality metric
Claude Opus 4.5
Gemini 2.5 Pro
Average Latency
Response time
Claude Opus 4.5
Gemini 2.5 Pro
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
| Metric | Claude Opus 4.5 | Gemini 2.5 Pro | Description |
|---|---|---|---|
| Overall Performance | |||
| ELO Rating | 1619 | 1429 | Overall ranking quality based on pairwise comparisons |
| Win Rate | 56.0% | 35.4% | Percentage of comparisons won against other models |
| Quality Score | 4.91 | 4.88 | Average quality across all RAG metrics |
| Pricing & Context | |||
| Input Price per 1M | $5.00 | $1.25 | Cost per million input tokens |
| Output Price per 1M | $25.00 | $10.00 | Cost per million output tokens |
| Context Window | 200K | 1049K | Maximum context window size |
| Release Date | 2025-11-24 | 2025-06-17 | Model release date |
| Performance Metrics | |||
| Avg Latency | 8.3s | 15.2s | Average response time across all datasets |
Dataset Performance
By benchmark
Comprehensive comparison of RAG quality metrics (correctness, faithfulness, grounding, relevance, completeness) and latency for each benchmark dataset.
MSMARCO
| Metric | Claude Opus 4.5 | Gemini 2.5 Pro | Description |
|---|---|---|---|
| Quality Metrics | |||
| Correctness | 4.97 | 4.90 | Factual accuracy of responses |
| Faithfulness | 4.97 | 4.93 | Adherence to source material |
| Grounding | 4.97 | 4.93 | Citations and context usage |
| Relevance | 4.97 | 5.00 | Query alignment and focus |
| Completeness | 4.97 | 4.90 | Coverage of all aspects |
| Overall | 4.97 | 4.93 | Average across all metrics |
| Latency Metrics | |||
| Mean | 5992ms | 12449ms | Average response time |
| Min | 2590ms | 7629ms | Fastest response time |
| Max | 8072ms | 23066ms | Slowest response time |
PG
| Metric | Claude Opus 4.5 | Gemini 2.5 Pro | Description |
|---|---|---|---|
| Quality Metrics | |||
| Correctness | 4.93 | 5.00 | Factual accuracy of responses |
| Faithfulness | 4.93 | 5.00 | Adherence to source material |
| Grounding | 4.93 | 5.00 | Citations and context usage |
| Relevance | 4.93 | 5.00 | Query alignment and focus |
| Completeness | 4.80 | 5.00 | Coverage of all aspects |
| Overall | 4.91 | 5.00 | Average across all metrics |
| Latency Metrics | |||
| Mean | 11489ms | 17834ms | Average response time |
| Min | 7945ms | 11067ms | Fastest response time |
| Max | 15934ms | 49308ms | Slowest response time |
SciFact
| Metric | Claude Opus 4.5 | Gemini 2.5 Pro | Description |
|---|---|---|---|
| Quality Metrics | |||
| Correctness | 4.73 | 4.73 | Factual accuracy of responses |
| Faithfulness | 4.80 | 4.80 | Adherence to source material |
| Grounding | 4.80 | 4.80 | Citations and context usage |
| Relevance | 4.97 | 4.73 | Query alignment and focus |
| Completeness | 4.70 | 4.57 | Coverage of all aspects |
| Overall | 4.80 | 4.73 | Average across all metrics |
| Latency Metrics | |||
| Mean | 7276ms | 15314ms | Average response time |
| Min | 4210ms | 8817ms | Fastest response time |
| Max | 10496ms | 35365ms | Slowest response time |
Explore More
Compare more LLMs
See how all LLMs stack up for RAG applications. Compare GPT-5, Claude, Gemini, and more. View comprehensive benchmarks and find the perfect LLM for your needs.