How does EventBridge Scheduler differ from EventBridge rules with schedules?

Scheduler offers several advantages: timezone support (rules only support UTC), one-time at() schedules, flexible time windows that randomly distribute invocations within a window, built-in retry policies with configurable attempts and DLQ, and the ability to invoke any AWS SDK API as a universal target. Scheduler also supports a much higher scale — millions of schedules per account vs. 300 rules per event bus. Use Scheduler for new scheduled tasks and EventBridge rules when you need event pattern matching.

What are flexible time windows?

A flexible time window is a duration (1-15 minutes) during which Scheduler randomly invokes the target. Instead of all schedules firing at exactly 9:00 AM, a 5-minute flexible window distributes invocations randomly between 9:00 and 9:05 AM. This prevents thundering herd effects where thousands of schedules trigger simultaneously, overwhelming downstream services. Flexible windows are optional — set the window to 'off' for precise timing requirements.

EventBridge Scheduler Builder

ServerlessAWS

Build EventBridge Scheduler one-time and recurring schedule configurations.

EventBridge Scheduler Configuration

Build EventBridge Scheduler one-time and recurring schedules with flexible time windows.

Required Fields

NameScheduleExpressionFlexibleTimeWindow.ModeTarget.ArnTarget.RoleArn

Generated Output

Output will appear here...

About This Tool

Amazon EventBridge Scheduler is a serverless scheduling service that lets you create one-time and recurring schedules to trigger over 270 AWS service API actions. Unlike EventBridge rules with cron expressions, Scheduler supports flexible time windows, automatic retries with dead-letter queues, and timezone-aware scheduling. It can invoke targets like Lambda functions, Step Functions, SQS queues, and any AWS SDK API action. The Scheduler Builder helps you configure schedule expressions (rate, cron, or one-time at()), target configurations, retry policies, and flexible time windows.

When to Use This Tool

•Creating timezone-aware recurring schedules that trigger Lambda functions at specific local times across global regions
•Building one-time schedules for delayed processing, such as sending a reminder email 24 hours after sign-up
•Configuring schedules with flexible time windows to spread invocations and avoid thundering herd problems

Frequently Asked Questions

How does EventBridge Scheduler differ from EventBridge rules with schedules?: Scheduler offers several advantages: timezone support (rules only support UTC), one-time at() schedules, flexible time windows that randomly distribute invocations within a window, built-in retry policies with configurable attempts and DLQ, and the ability to invoke any AWS SDK API as a universal target. Scheduler also supports a much higher scale — millions of schedules per account vs. 300 rules per event bus. Use Scheduler for new scheduled tasks and EventBridge rules when you need event pattern matching.
What are flexible time windows?: A flexible time window is a duration (1-15 minutes) during which Scheduler randomly invokes the target. Instead of all schedules firing at exactly 9:00 AM, a 5-minute flexible window distributes invocations randomly between 9:00 and 9:05 AM. This prevents thundering herd effects where thousands of schedules trigger simultaneously, overwhelming downstream services. Flexible windows are optional — set the window to 'off' for precise timing requirements.

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