EventBridge Pattern Tester - Test Event Patterns Against Multiple Sample Events

First Published:
Last Updated:

Test AWS EventBridge event patterns against multiple sample events at once. Get exact match/no-match results plus the failing key for each event - faster than the AWS console Sandbox when iterating on filters.

All processing is performed entirely in your browser using client-side JavaScript. No data is transmitted to any server. Your event patterns and sample events never leave your device.

  • This tool is provided "AS IS" without any warranties of any kind.
  • The author accepts no responsibility for incorrect routing decisions made based on its output.
  • Always validate critical EventBridge rules in a non-production environment before deploying them.
  • By using this tool, you accept full responsibility for any outcomes.

This tool uses client-side JavaScript for all processing. No data is transmitted to servers, no files are uploaded online, all processing happens locally in your browser. Once loaded, this tool continues to work even without an internet connection. For more details, please refer to our Web Tools Disclaimer.

Load a preset
A single EventBridge event pattern object.
JSON array of events, a single event object, or one JSON event per line (JSON Lines).

Features

  • Batch Testing: Evaluate one event pattern against many sample events in a single run.
  • Failure Reasons: For every "No Match" result, see exactly which key and which rule caused the mismatch.
  • AWS-Compatible Filters: Supports literal equality, multi-value OR, exists, prefix, suffix, anything-but, numeric, cidr (IPv4), wildcard, equals-ignore-case, nested objects, and the $or operator.
  • Flexible Input: Sample events can be a JSON array, a single object, or JSON Lines (one event per line).
  • Presets: One-click templates for S3 Object Created, EC2 State Change, CloudWatch Alarm State Change, and a custom event with mixed filters.
  • Privacy: Everything runs locally in your browser. No event data is sent anywhere.

How to Use

  1. Click a preset button to load a working example, or paste your own Event Pattern JSON in the left textarea.
  2. Paste one or more sample events in the right textarea (JSON array, single object, or JSON Lines).
  3. Click Test Match. The summary shows totals; the table shows per-event Match / No Match status with the failing key for unmatched events.
  4. Expand View event JSON on any row to inspect the original event.
  5. Use Copy Results to copy a summary text to the clipboard, or Clear All to reset.

Important Notes

  • Out of scope (MVP): Input Transformer testing, Archive / Replay, Schema Registry integration are not implemented.
  • CIDR support is IPv4 only. IPv6 CIDR blocks are not evaluated.
  • Wildcard: Only the * wildcard character is supported, matching AWS EventBridge behavior. ? and other glob characters are treated as literals.
  • Numeric: Operators =, >, >=, <, <= are supported, as documented in the EventBridge content filtering reference.
  • Best effort: This tool implements the documented EventBridge content filtering rules but does not guarantee full parity with the AWS service for every undocumented edge case. Validate critical rules with the AWS console Sandbox before relying on them in production.

References:
Tech Blog with curated related content
Web Tools Collection

Written by Hidekazu Konishi