Cron式パーサー
Cronスケジュール式の解析と視覚化
* - Any value
1-5 - Range of values
*/5 - Every 5th value
1,3,5 - Multiple values
使い方
テキストを貼り付けまたは入力
テキスト、コード、またはデータを入力エリアに入力します。
オプションを選択
適用する変換やフォーマットを選択します。
結果をコピー
ワンクリックで出力をクリップボードにコピーします。
このツールを使う理由
完全無料
隠れたコストもプレミアムプランもありません — すべての機能が無料です。
インストール不要
すべてブラウザで実行されます。ソフトウェアのダウンロードやインストールは不要です。
プライベート＆安全
データはデバイスの外に出ることはありません。サーバーにアップロードされることはありません。
モバイル対応
完全レスポンシブ対応 — スマートフォン、タブレット、デスクトップで利用できます。
Cron Expression Syntax for Scheduled Task Automation
Key Takeaways
- Cron expressions define recurring schedules using five fields: minute, hour, day of month, month, and day of week.
- Understanding cron syntax is essential for scheduling jobs in Linux, CI/CD pipelines, cloud functions, and task automation systems.
- All cron parsing happens in your browser — your scheduling data is never sent to any server.
Cron is the standard time-based job scheduling system in Unix-like operating systems, and its expression syntax has been adopted across the technology ecosystem. From Linux crontab to GitHub Actions schedules, AWS CloudWatch rules, and Kubernetes CronJobs, cron expressions are the universal language for defining recurring schedules. Parsing and validating these expressions prevents costly scheduling errors.
Cron syntax is supported by all major cloud platforms: AWS, GCP, Azure, and every CI/CD system.
Universal Adoption
Key Concepts
Five-Field Format
Standard cron: minute (0-59), hour (0-23), day of month (1-31), month (1-12), day of week (0-7 where 0 and 7 are Sunday). Extended formats add a seconds field.
Special Characters
Asterisk (*) means every value. Comma (,) lists values. Hyphen (-) defines ranges. Slash (/) sets intervals. Example: */15 means every 15 units.
Common Patterns
Daily at midnight: 0 0 * * *. Every 5 minutes: */5 * * * *. Weekdays at 9am: 0 9 * * 1-5. First of month: 0 0 1 * *. These patterns cover 90% of scheduling needs.
Platform Variations
AWS uses 6 fields (adding year). Some systems support @yearly, @monthly, @weekly, @daily, @hourly shortcuts. Kubernetes uses standard 5-field format. Always check your platform's documentation.
Pro Tips
Always test cron expressions by checking the next 5-10 run times to verify the schedule matches your expectations.
Use descriptive comments alongside cron entries to explain the purpose — future you will thank present you.
Be careful with day-of-month and day-of-week combined — in most implementations, they form an OR condition, not AND.
Account for timezone differences — cron typically runs in the server's local time unless UTC is explicitly specified.
All cron expression parsing is performed entirely in your browser. Your scheduling configurations are never transmitted to any external server.