Cohere Rerank 4 Fast vs Contextual AI Rerank v2 Instruct
Detailed comparison between Cohere Rerank 4 Fast and Contextual AI Rerank v2 Instruct. See which reranker best meets your accuracy and performance needs.
Model Comparison
Cohere Rerank 4 Fast takes the lead.
Both Cohere Rerank 4 Fast and Contextual AI Rerank v2 Instruct are powerful reranking models designed to improve retrieval quality in RAG applications. However, their performance characteristics differ in important ways.
Why Cohere Rerank 4 Fast:
- Cohere Rerank 4 Fast has 46 higher ELO rating
- Cohere Rerank 4 Fast is 2887ms faster on average
- Cohere Rerank 4 Fast has a 7.0% higher win rate
Overview
Key metrics
ELO Rating
Overall ranking quality
Cohere Rerank 4 Fast
Contextual AI Rerank v2 Instruct
Win Rate
Head-to-head performance
Cohere Rerank 4 Fast
Contextual AI Rerank v2 Instruct
Accuracy (nDCG@10)
Ranking quality metric
Cohere Rerank 4 Fast
Contextual AI Rerank v2 Instruct
Average Latency
Response time
Cohere Rerank 4 Fast
Contextual AI Rerank v2 Instruct
Visual Performance Analysis
Performance
ELO Rating Comparison
Win/Loss/Tie Breakdown
Latency Distribution (ms)
Breakdown
How the models stack up
| Metric | Cohere Rerank 4 Fast | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Overall Performance | |||
| ELO Rating | 1506 | 1461 | Overall ranking quality based on pairwise comparisons |
| Win Rate | 49.3% | 42.3% | Percentage of comparisons won against other models |
| Pricing & Availability | |||
| Price per 1M tokens | $0.050 | $0.050 | Cost per million tokens processed |
| Release Date | 2025-12-11 | 2025-09-12 | Model release date |
| Accuracy Metrics | |||
| Avg nDCG@10 | N/A | 0.114 | Normalized discounted cumulative gain at position 10 |
| Performance Metrics | |||
| Avg Latency | 447ms | 3333ms | Average response time across all datasets |
Dataset Performance
By field
Comprehensive comparison of accuracy metrics (nDCG, Recall) and latency percentiles for each benchmark dataset.
MSMARCO
| Metric | Cohere Rerank 4 Fast | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 403ms | 3283ms | Average response time |
| P50 | 382ms | 3260ms | 50th percentile (median) |
| P90 | 486ms | 3885ms | 90th percentile |
arguana
| Metric | Cohere Rerank 4 Fast | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 574ms | 3627ms | Average response time |
| P50 | 562ms | 3601ms | 50th percentile (median) |
| P90 | 728ms | 4037ms | 90th percentile |
FiQa
| Metric | Cohere Rerank 4 Fast | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 485ms | 3283ms | Average response time |
| P50 | 459ms | 3209ms | 50th percentile (median) |
| P90 | 624ms | 3891ms | 90th percentile |
business reports
| Metric | Cohere Rerank 4 Fast | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 428ms | 3231ms | Average response time |
| P50 | 408ms | 3129ms | 50th percentile (median) |
| P90 | 550ms | 3651ms | 90th percentile |
PG
| Metric | Cohere Rerank 4 Fast | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 492ms | 3566ms | Average response time |
| P50 | 439ms | 3475ms | 50th percentile (median) |
| P90 | 650ms | 4148ms | 90th percentile |
DBPedia
| Metric | Cohere Rerank 4 Fast | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 297ms | 3010ms | Average response time |
| P50 | 297ms | 3042ms | 50th percentile (median) |
| P90 | 309ms | 3283ms | 90th percentile |
Explore More
Compare more rerankers
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