AWSAmazon KendraAnalytics

`aws_kendra_index` cost estimation

A managed intelligent-search index. Priced as a flat hourly fee by edition, billed continuously, with a substantial monthly floor.

An aws_kendra_index is Amazon's managed enterprise-search service with ML-powered relevance and natural-language queries. Unlike usage-metered search, Kendra is priced as a provisioned index: a flat hourly rate by edition, billed continuously whether or not anyone queries it.

The Developer edition runs about $810/month and is intended for proof-of-concept (lower capacity, no SLA). The Enterprise edition is about $1,008/month per index unit and adds capacity, redundancy, and an SLA. Both include a base capacity of documents and queries; scaling beyond it adds storage and query capacity units at additional hourly cost. There is no scale-to-zero, so the edition's monthly figure is a hard floor.

c3x reads the edition and prices the index-hours at 730 hours/month. Additional capacity units are usage-based and supplied in c3x-usage.yml. Kendra's floor surprises teams who spin up a Developer index to evaluate and leave it running, that's $810/month for an idle index, so the estimate is a useful guardrail.

Terraform example

A minimal but realistic configuration that C3X can estimate.

resource "aws_kendra_index" "docs" {
  name     = "support-docs"
  edition  = "DEVELOPER_EDITION"
  role_arn = aws_iam_role.kendra.arn
}

Pricing dimensions

What you actually pay for when you provision aws_kendra_index.

Dimension	Unit	What's being charged
Index hours	per hour	Flat hourly rate by edition, billed continuously. c3x reads edition and assumes 730 hours/month. ~$1.11/hour Developer (~$810/mo), ~$1.40/hour Enterprise (~$1,008/mo)
Additional capacity units	per unit-hour	Extra storage and query capacity beyond the base. Usage-based; define in c3x-usage.yml.

Sample C3X output

Example output from c3x estimate (Developer edition):

aws_kendra_index.docs
└─ Index (Developer edition)   730  hours    $810.00

OVERALL TOTAL                                $810.00

Optimization tips

Common ways to reduce aws_kendra_index cost without changing the workload.

Delete Developer indexes after evaluation

$810/month per idle index

Kendra bills continuously with no scale-to-zero. A Developer index left running after a POC quietly costs $810/month. Tear down evaluation indexes.

Use Developer edition for non-production

~$200/month per index

Enterprise adds capacity, redundancy, and an SLA at ~25% more. For internal tools or staging, Developer edition is sufficient and cheaper.

Consider OpenSearch for keyword-only search

Workload-dependent

If you don't need Kendra's ML relevance and natural-language understanding, an OpenSearch domain delivers keyword and vector search at lower cost. Match the tool to the search sophistication you actually need.

FAQ

How does c3x estimate Kendra cost?

It reads the edition and prices the index-hours at 730 hours/month (~$810 Developer, ~$1,008 Enterprise). Additional capacity units are usage-based and supplied in c3x-usage.yml.

Why does an idle Kendra index cost over $800/month?

Kendra is a provisioned index billed by the hour continuously, not per query. There's no scale-to-zero, so the edition's monthly rate applies regardless of query volume.

What's the difference between the editions?

Developer (~$810/mo) is for POCs, with lower capacity and no SLA. Enterprise (~$1,008/mo per index unit) adds capacity, redundancy, and an availability SLA for production.

Are documents and queries billed separately?

Each edition includes a base capacity of documents and queries. Beyond that, additional storage and query capacity units bill per hour. c3x prices the base from the edition and treats extra units as usage-based.

Is Kendra worth it over OpenSearch?

Kendra adds ML-driven relevance, natural-language queries, and connectors at a high fixed cost. For straightforward keyword or vector search, OpenSearch is cheaper. Kendra earns its floor when the intelligent-search features matter.