Zerank 1 Small vs Contextual AI Rerank v2 Instruct
Detailed comparison between Zerank 1 Small and Contextual AI Rerank v2 Instruct. See which reranker best meets your accuracy and performance needs.
Model Comparison
Zerank 1 Small takes the lead.
Both Zerank 1 Small 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 Zerank 1 Small:
- Zerank 1 Small has 75 higher ELO rating
- Zerank 1 Small is 3086ms faster on average
- Zerank 1 Small has a 13.5% higher win rate
Overview
Key metrics
ELO Rating
Overall ranking quality
Zerank 1 Small
Contextual AI Rerank v2 Instruct
Win Rate
Head-to-head performance
Zerank 1 Small
Contextual AI Rerank v2 Instruct
Accuracy (nDCG@10)
Ranking quality metric
Zerank 1 Small
Contextual AI Rerank v2 Instruct
Average Latency
Response time
Zerank 1 Small
Contextual AI Rerank v2 Instruct
Visual Performance Analysis
Performance
ELO Rating Comparison
Win/Loss/Tie Breakdown
Accuracy Across Datasets (nDCG@10)
Latency Distribution (ms)
Breakdown
How the models stack up
| Metric | Zerank 1 Small | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Overall Performance | |||
| ELO Rating | 1556 | 1481 | Overall ranking quality based on pairwise comparisons |
| Win Rate | 58.6% | 45.1% | Percentage of comparisons won against other models |
| Pricing & Availability | |||
| Price per 1M tokens | $0.025 | $0.050 | Cost per million tokens processed |
| Release Date | 2025-07-10 | 2025-09-12 | Model release date |
| Accuracy Metrics | |||
| Avg nDCG@10 | 0.083 | 0.114 | Normalized discounted cumulative gain at position 10 |
| Performance Metrics | |||
| Avg Latency | 248ms | 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 | Zerank 1 Small | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 217ms | 3283ms | Average response time |
| P50 | 214ms | 3260ms | 50th percentile (median) |
| P90 | 227ms | 3885ms | 90th percentile |
arguana
| Metric | Zerank 1 Small | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.279 | 0.525 | Ranking quality at top 5 results |
| nDCG@10 | 0.375 | 0.560 | Ranking quality at top 10 results |
| Recall@5 | 0.520 | 0.860 | % of relevant docs in top 5 |
| Recall@10 | 0.820 | 0.960 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 256ms | 3627ms | Average response time |
| P50 | 254ms | 3601ms | 50th percentile (median) |
| P90 | 280ms | 4037ms | 90th percentile |
FiQa
| Metric | Zerank 1 Small | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.114 | 0.119 | Ranking quality at top 5 results |
| nDCG@10 | 0.124 | 0.125 | Ranking quality at top 10 results |
| Recall@5 | 0.098 | 0.123 | % of relevant docs in top 5 |
| Recall@10 | 0.125 | 0.135 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 248ms | 3283ms | Average response time |
| P50 | 244ms | 3209ms | 50th percentile (median) |
| P90 | 266ms | 3891ms | 90th percentile |
business reports
| Metric | Zerank 1 Small | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 251ms | 3231ms | Average response time |
| P50 | 242ms | 3129ms | 50th percentile (median) |
| P90 | 298ms | 3651ms | 90th percentile |
PG
| Metric | Zerank 1 Small | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 287ms | 3566ms | Average response time |
| P50 | 274ms | 3475ms | 50th percentile (median) |
| P90 | 345ms | 4148ms | 90th percentile |
DBPedia
| Metric | Zerank 1 Small | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 226ms | 3010ms | Average response time |
| P50 | 223ms | 3042ms | 50th percentile (median) |
| P90 | 241ms | 3283ms | 90th percentile |
Explore More
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