Amazon Comprehend Pricing Calculator
Estimate NLP units for entity detection, PII redaction, and custom classification — the preprocessing layer your Bedrock bill assumes is free.
- No signup
- Instant results
- ~3 min
Rates reviewed
Feature
us-east-1list rates, pricing as of 2026-07-05. Bedrock inference not included. Source: AWS public pricing.
Who This Tool Is For
ML engineers and compliance teams scrubbing documents before Bedrock ingestion or building non-LLM NLP pipelines.
Why We Built This Tool
Comprehend charges per 100-character unit with different rates for PII, custom models, and async batch vs sync real-time endpoints.
What Problem It Solves
- Unit minimum. Every request bills at least 3 units (300 characters) even for short text.
- Endpoint idle cost. Sync endpoints bill per second while running, regardless of request volume.
- No Bedrock overlap. This estimate excludes LLM token costs — model those separately.
See Generative AI on AWS or Bedrock pricing.
Frequently Asked Questions
How is a Comprehend NLP unit calculated?
One unit equals 100 characters, rounded up per request, with a 3-unit (300 character) minimum. A 550-character document uses 6 units.
Is PII detection priced differently from entity detection?
Detect PII uses the same $0.0001/unit rate as standard entity recognition. Contains PII is much cheaper at $0.000002/unit because it returns a boolean.
When is async batch cheaper than real-time?
Async batch suits bulk preprocessing pipelines. Sync endpoints win when you need sub-second latency and can keep utilization high enough to amortize idle time.
Do custom Comprehend endpoints run 24/7?
You pay from endpoint creation until deletion at $0.0005/second per inference unit — schedule endpoints down outside peak hours to cut cost.
Comprehend vs Macie for S3 PII — cost tradeoff?
Macie discovers PII in S3 buckets at scale; Comprehend redacts inline text before indexing. Use Macie for inventory and Comprehend for document pipelines.
Where do these prices come from?
Rates are AWS published us-east-1 list prices (Amazon Comprehend pricing), pricing as of 2026-07-05.