Amazon SQS Pricing

Standard Queue

High Throughput: Standard queues have nearly-unlimited transactions per second (TPS).

At-Least-Once Delivery: A message is delivered at least once, but occasionally more than one copy of a message is delivered.

Best-Effort Ordering: Occasionally, messages might be delivered in an order different from which they were sent.

Send data between applications when the throughput is important, for example:

• Decouple live user requests from intensive background work: let users upload media while resizing or encoding it.
• Allocate tasks to multiple worker nodes: process a high number of credit card validation requests.
• Batch messages for future processing: schedule multiple entries to be added to a database.

FIFO Queue

First-In-First-Out Delivery: The order in which messages are sent and received is strictly preserved.

Exactly-Once Processing: A message is delivered once and remains available until a consumer processes and deletes it. Duplicates are not introduced into the queue.

Limited Throughput: 300 transactions per second (TPS).

Send data between applications when the order of events is important, for example:

• Ensure that user-entered commands are executed in the right order.
• Display the correct product price by sending price modifications in the right order.
• Prevent a student from enrolling in a course before registering for an account.