AWS Data Exchange vs public APIs

Short answer:
Use AWS Data Exchange when you want to buy, subscribe to, govern, and automate delivery of third‑party data in AWS.
Use public APIs when you want direct, programmatic access to an online service’s data/features and you’re okay integrating, throttling, authenticating, and handling data collection yourself.

AWS Data Exchange

Best for:

• Licensed datasets from providers
• Scheduled, repeatable delivery of files/feeds
• Centralized billing/subscription management
• Compliance/governance and auditability
• Data you want to land in AWS services/S3 for analytics or ML

Pros:

• Managed subscription workflow
• Easier procurement/legal controls
• Standardized dataset delivery
• Good for bulk data, not just real-time lookups

Cons:

• Only works for data providers that publish there
• Less flexible than an API
• Often batch-oriented, not low-latency
• Can be more expensive/indirect than direct access

Public APIs

Best for:

• Real-time or near-real-time requests
• Small, frequent queries
• Direct integration with a vendor’s service
• Custom workflows and event-driven apps

Pros:

• Immediate access to live data/actions
• Flexible and widely available
• Fine for application integrations

Cons:

• You build auth, retries, pagination, rate limiting, data normalization
• Terms of use may restrict storage/redistribution
• Can be fragile if API versions change
• Not ideal for large-scale historical datasets

Rule of thumb

• Need bulk, licensed, managed data delivery? → AWS Data Exchange
• Need live service calls or operational integration? → Public API

Example

• Market data/history, geospatial datasets, demographic data → AWS Data Exchange
• Weather now, stock quote lookup, SaaS app integration, maps/geocoding → Public API

If you want, I can also give you a decision matrix or compare them for a specific use case like financial data, ML training, or ETL pipelines.