Cohere Rerank 4 Fast

Cohere's lower-latency Rerank 4 option for high-volume search, recommendations, and RAG retrieval.

Plain-English overview

What Cohere Rerank 4 Fast actually is

Rerank 4 Fast uses the same basic workflow as Pro: retrieve a candidate set first, then ask the reranker to move the most useful results to the top. It supports multilingual text and semi-structured JSON with the same extended context.

Fast is the operational choice when traffic, response time, and cost carry more weight than squeezing out the strongest possible ordering. The shared API shape makes it practical to test Fast and Pro on the same real queries before deciding.

Good fit for

High-throughput product search
Latency-sensitive RAG applications
Teams A/B testing speed and retrieval quality

Category comparison

The facts that matter for reranking models

These are provider-published specifications, not Cody benchmark scores. Follow the linked sources for current limits and endpoint-specific exceptions.

Price basis: $2 / 1K searches; up to 100 docs per unitThe provider's billing unit, with the document or token assumptions needed to compare it fairly.
Text capacity: 32,768 tokens per query-document passHow much query and candidate text the model can consider in one scoring pass.
Candidates per request: Up to 10,000 documents per requestThe maximum number of possible results accepted in one request, when the provider publishes it.
Language coverage: Multilingual; exact count not publishedPublished multilingual support; an exact count is shown only when the provider gives one.
Structured data: Text and semi-structured JSONWhether the model is documented for JSON, tables, XML, or other data beyond normal prose.
Where it runs: Cohere API; enterprise private and cloud optionsHosted API, cloud marketplace, private deployment, or self-hosted weights.

API and provider access

Where to get Cohere Rerank 4 Fast

CohereCohere Rerank documentationDirect API model selection and request behavior.CohereCohere pricingLive search-unit price and billing definition.

Availability

Regions and access stage

Available through Cohere's Rerank API, with enterprise deployment choices that can bring the model closer to private data.

Hosted and private-deployment regions depend on the selected Cohere route and agreement.

Check live availability

Data and training

The route matters.

This is a concise reading of the cited provider material, not legal advice. A third-party gateway can have different storage, routing, training, and residency terms from the model maker's direct API.

Read the provider policy

Frequently asked questions

Cohere Rerank 4 Fast FAQ

What is Cohere Rerank 4 Fast?

Cohere's lower-latency Rerank 4 option for high-volume search, recommendations, and RAG retrieval. Rerank 4 Fast uses the same basic workflow as Pro: retrieve a candidate set first, then ask the reranker to move the most useful results to the top. It supports multilingual text and semi-structured JSON with the same extended context.

When was Cohere Rerank 4 Fast released?

Cohere Rerank 4 Fast was released on December 11, 2025 according to the cited provider materials.

Where can I access Cohere Rerank 4 Fast?

Available through Cohere's Rerank API, with enterprise deployment choices that can bring the model closer to private data. The access routes listed in this guide are Cohere.

How much does Cohere Rerank 4 Fast cost?

$2 / 1,000 searches. One search unit covers one query against up to 100 documents. Longer documents can be split into extra billable chunks.

Where is Cohere Rerank 4 Fast available?

Available through Cohere's Rerank API, with enterprise deployment choices that can bring the model closer to private data. Hosted and private-deployment regions depend on the selected Cohere route and agreement.

Is my Cohere Rerank 4 Fast API data used for training?

Cohere enterprise customers can opt out of training; SaaS prompts and generations are generally deleted after 30 days. Approved zero-data-retention accounts and private or third-party deployments offer stronger controls. The policy belongs to the provider route and account terms, so verify it again before production use.

Related comparisons

Head-to-head comparisons

View category →