Cohere Rerank 4 Fast vs Cohere Rerank 3.5
Detailed comparison between Cohere Rerank 4 Fast and Cohere Rerank 3.5. See which reranker best meets your accuracy and performance needs. If you want to compare these models on your data, try Agentset.
Model Comparison
Cohere Rerank 4 Fast takes the lead.
Both Cohere Rerank 4 Fast and Cohere Rerank 3.5 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 59 higher ELO rating
- Cohere Rerank 4 Fast delivers better accuracy (nDCG@10: 0.094 vs 0.080)
- Cohere Rerank 4 Fast has a 8.9% higher win rate
Overview
Key metrics
ELO Rating
Overall ranking quality
Cohere Rerank 4 Fast
Cohere Rerank 3.5
Win Rate
Head-to-head performance
Cohere Rerank 4 Fast
Cohere Rerank 3.5
Accuracy (nDCG@10)
Ranking quality metric
Cohere Rerank 4 Fast
Cohere Rerank 3.5
Average Latency
Response time
Cohere Rerank 4 Fast
Cohere Rerank 3.5
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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 | Cohere Rerank 4 Fast | Cohere Rerank 3.5 | Description |
|---|---|---|---|
| Overall Performance | |||
| ELO Rating | 1510 | 1451 | Overall ranking quality based on pairwise comparisons |
| Win Rate | 49.8% | 40.9% | 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 | 2024-12-02 | Model release date |
| Accuracy Metrics | |||
| Avg nDCG@10 | 0.094 | 0.080 | Normalized discounted cumulative gain at position 10 |
| Performance Metrics | |||
| Avg Latency | 447ms | 392ms | 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 | Cohere Rerank 4 Fast | Cohere Rerank 3.5 | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 403ms | 339ms | Average response time |
| P50 | 382ms | 285ms | 50th percentile (median) |
| P90 | 486ms | 304ms | 90th percentile |
arguana
| Metric | Cohere Rerank 4 Fast | Cohere Rerank 3.5 | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.351 | 0.267 | Ranking quality at top 5 results |
| nDCG@10 | 0.425 | 0.355 | Ranking quality at top 10 results |
| Recall@5 | 0.660 | 0.520 | % of relevant docs in top 5 |
| Recall@10 | 0.880 | 0.800 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 574ms | 570ms | Average response time |
| P50 | 562ms | 373ms | 50th percentile (median) |
| P90 | 728ms | 617ms | 90th percentile |
FiQa
| Metric | Cohere Rerank 4 Fast | Cohere Rerank 3.5 | Description |
|---|---|---|---|
| Accuracy Metrics | |||
| nDCG@5 | 0.135 | 0.124 | Ranking quality at top 5 results |
| nDCG@10 | 0.138 | 0.128 | Ranking quality at top 10 results |
| Recall@5 | 0.125 | 0.123 | % of relevant docs in top 5 |
| Recall@10 | 0.130 | 0.130 | % of relevant docs in top 10 |
| Latency Metrics | |||
| Mean | 485ms | 364ms | Average response time |
| P50 | 459ms | 315ms | 50th percentile (median) |
| P90 | 624ms | 401ms | 90th percentile |
business reports
| Metric | Cohere Rerank 4 Fast | Cohere Rerank 3.5 | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 428ms | 334ms | Average response time |
| P50 | 408ms | 293ms | 50th percentile (median) |
| P90 | 550ms | 503ms | 90th percentile |
PG
| Metric | Cohere Rerank 4 Fast | Cohere Rerank 3.5 | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 492ms | 458ms | Average response time |
| P50 | 439ms | 360ms | 50th percentile (median) |
| P90 | 650ms | 615ms | 90th percentile |
DBPedia
| Metric | Cohere Rerank 4 Fast | Cohere Rerank 3.5 | Description |
|---|---|---|---|
| Latency Metrics | |||
| Mean | 297ms | 286ms | Average response time |
| P50 | 297ms | 279ms | 50th percentile (median) |
| P90 | 309ms | 290ms | 90th percentile |
Explore More
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