Zerank 1 vs Contextual AI Rerank v2 Instruct
Detailed comparison between Zerank 1 and Contextual AI Rerank v2 Instruct. See which reranker best meets your accuracy and performance needs.
Model Comparison
Zerank 1 takes the lead.
Both Zerank 1 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:
- Zerank 1 has 113 higher ELO rating
- Zerank 1 is 3067ms faster on average
- Zerank 1 has a 15.0% higher win rate
Overview
Key metrics
ELO Rating
Overall ranking quality
Zerank 1
Contextual AI Rerank v2 Instruct
Win Rate
Head-to-head performance
Zerank 1
Contextual AI Rerank v2 Instruct
Accuracy (nDCG@10)
Ranking quality metric
Zerank 1
Contextual AI Rerank v2 Instruct
Average Latency
Response time
Zerank 1
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 | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Overall Performance | |||
| ELO Rating | 1574 | 1461 | Overall ranking quality based on pairwise comparisons |
| Win Rate | 57.3% | 42.3% | 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 | 0.192 | 0.230 | Normalized discounted cumulative gain at position 10 |
| Performance Metrics | |||
| Avg Latency | 266ms | 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 | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.439 | 0.510 | Ranking quality at top 5 results |
| nDCG@10 | 0.499 | 0.538 | Ranking quality at top 10 results |
| Recall@5 | 0.600 | 0.720 | % of relevant docs in top 5 |
| Recall@10 | 0.780 | 0.800 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 232ms | 3283ms | Average response time |
| P50 | 226ms | 3260ms | 50th percentile (median) |
| P90 | 245ms | 3885ms | 90th percentile |
arguana
| Metric | Zerank 1 | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.308 | 0.525 | Ranking quality at top 5 results |
| nDCG@10 | 0.369 | 0.560 | Ranking quality at top 10 results |
| Recall@5 | 0.580 | 0.860 | % of relevant docs in top 5 |
| Recall@10 | 0.760 | 0.960 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 287ms | 3627ms | Average response time |
| P50 | 275ms | 3601ms | 50th percentile (median) |
| P90 | 332ms | 4037ms | 90th percentile |
FiQa
| Metric | Zerank 1 | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.115 | 0.119 | Ranking quality at top 5 results |
| nDCG@10 | 0.121 | 0.125 | Ranking quality at top 10 results |
| Recall@5 | 0.105 | 0.123 | % of relevant docs in top 5 |
| Recall@10 | 0.125 | 0.135 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 259ms | 3283ms | Average response time |
| P50 | 258ms | 3209ms | 50th percentile (median) |
| P90 | 276ms | 3891ms | 90th percentile |
business reports
| Metric | Zerank 1 | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 289ms | 3231ms | Average response time |
| P50 | 272ms | 3129ms | 50th percentile (median) |
| P90 | 363ms | 3651ms | 90th percentile |
PG
| Metric | Zerank 1 | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 293ms | 3566ms | Average response time |
| P50 | 279ms | 3475ms | 50th percentile (median) |
| P90 | 348ms | 4148ms | 90th percentile |
DBPedia
| Metric | Zerank 1 | Contextual AI Rerank v2 Instruct | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.145 | 0.158 | Ranking quality at top 5 results |
| nDCG@10 | 0.161 | 0.159 | Ranking quality at top 10 results |
| Recall@5 | 0.004 | 0.004 | % of relevant docs in top 5 |
| Recall@10 | 0.005 | 0.005 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 238ms | 3010ms | Average response time |
| P50 | 233ms | 3042ms | 50th percentile (median) |
| P90 | 257ms | 3283ms | 90th percentile |
Explore More
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