Zerank 1 Small vs Cohere Rerank 4 Fast
Detailed comparison between Zerank 1 Small and Cohere Rerank 4 Fast. See which reranker best meets your accuracy and performance needs. If you want to compare these models on your data, try Agentset.
Model Comparison
Zerank 1 Small takes the lead.
Both Zerank 1 Small and Cohere Rerank 4 Fast 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 29 higher ELO rating
- Zerank 1 Small is 199ms faster on average
- Zerank 1 Small has a 5.2% higher win rate
Overview
Key metrics
ELO Rating
Overall ranking quality
Zerank 1 Small
Cohere Rerank 4 Fast
Win Rate
Head-to-head performance
Zerank 1 Small
Cohere Rerank 4 Fast
Accuracy (nDCG@10)
Ranking quality metric
Zerank 1 Small
Cohere Rerank 4 Fast
Average Latency
Response time
Zerank 1 Small
Cohere Rerank 4 Fast
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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 | Cohere Rerank 4 Fast | Description |
|---|---|---|---|
| Overall Performance | |||
| ELO Rating | 1539 | 1510 | Overall ranking quality based on pairwise comparisons |
| Win Rate | 55.0% | 49.8% | 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 | 2025-12-11 | Model release date |
| Accuracy Metrics | |||
| Avg nDCG@10 | 0.083 | 0.094 | Normalized discounted cumulative gain at position 10 |
| Performance Metrics | |||
| Avg Latency | 248ms | 447ms | Average response time across all datasets |
Build RAG in Minutes, Not Months
Agentset gives you a complete RAG API with top-ranked rerankers and embedding models built in. Upload your data, call the API, and get accurate results from day one.
import { Agentset } from "agentset";
const agentset = new Agentset();
const ns = agentset.namespace("ns_1234");
const results = await ns.search(
"What is multi-head attention?"
);
for (const result of results) {
console.log(result.text);
}Dataset Performance
By field
Comprehensive comparison of accuracy metrics (nDCG, Recall) and latency percentiles for each benchmark dataset.
MSMARCO
| Metric | Zerank 1 Small | Cohere Rerank 4 Fast | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 217ms | 403ms | Average response time |
| P50 | 214ms | 382ms | 50th percentile (median) |
| P90 | 227ms | 486ms | 90th percentile |
arguana
| Metric | Zerank 1 Small | Cohere Rerank 4 Fast | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.279 | 0.351 | Ranking quality at top 5 results |
| nDCG@10 | 0.375 | 0.425 | Ranking quality at top 10 results |
| Recall@5 | 0.520 | 0.660 | % of relevant docs in top 5 |
| Recall@10 | 0.820 | 0.880 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 256ms | 574ms | Average response time |
| P50 | 254ms | 562ms | 50th percentile (median) |
| P90 | 280ms | 728ms | 90th percentile |
FiQa
| Metric | Zerank 1 Small | Cohere Rerank 4 Fast | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.114 | 0.135 | Ranking quality at top 5 results |
| nDCG@10 | 0.124 | 0.138 | Ranking quality at top 10 results |
| Recall@5 | 0.098 | 0.125 | % of relevant docs in top 5 |
| Recall@10 | 0.125 | 0.130 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 248ms | 485ms | Average response time |
| P50 | 244ms | 459ms | 50th percentile (median) |
| P90 | 266ms | 624ms | 90th percentile |
business reports
| Metric | Zerank 1 Small | Cohere Rerank 4 Fast | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 251ms | 428ms | Average response time |
| P50 | 242ms | 408ms | 50th percentile (median) |
| P90 | 298ms | 550ms | 90th percentile |
PG
| Metric | Zerank 1 Small | Cohere Rerank 4 Fast | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 287ms | 492ms | Average response time |
| P50 | 274ms | 439ms | 50th percentile (median) |
| P90 | 345ms | 650ms | 90th percentile |
DBPedia
| Metric | Zerank 1 Small | Cohere Rerank 4 Fast | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 226ms | 297ms | Average response time |
| P50 | 223ms | 297ms | 50th percentile (median) |
| P90 | 241ms | 309ms | 90th percentile |
Explore More
Compare more rerankers
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