Gerador Cron
Em alta 🔥Construir e explicar expressões cron
Como usar Gerador Cron
- 1Use o construtor visual para selecionar o horário
- 2Ou digite a expressão Cron diretamente
- 3Veja a explicação legível por humanos
- 4Verifique os próximos horários de execução
Sobre Gerador Cron
O gerador Cron é uma ferramenta para criar e entender expressões Cron para agendamento de tarefas.
Principais recursos de Gerador Cron
- Visual cron expression builder with controls for each field
- Generates standard 5-field cron expressions (minute hour dom month dow)
- Human-readable explanation of the generated schedule
- Shows the next 5–10 scheduled run times based on current time
- Includes common presets (hourly, daily, weekly, monthly)
- Compatible with Unix crontab, GitHub Actions, AWS EventBridge, and Kubernetes
- Works entirely in-browser — no server required
- One-click copy of the generated expression
Exemplos
Schedule a daily backup at 2 AM
Create a cron expression to run a backup script every day at 2:00 AM.
Entrada
Minute: 0, Hour: 2, Day: *, Month: *, Weekday: *
Saída
Cron: 0 2 * * * — Explanation: Every day at 02:00
Run a job every weekday at 9 AM
Schedule a morning report to run on Monday through Friday at 9 AM.
Entrada
Minute: 0, Hour: 9, Day: *, Month: *, Weekday: 1-5
Saída
Cron: 0 9 * * 1-5 — Explanation: At 09:00 on Monday through Friday
Casos de uso comuns
- Scheduling database backup scripts via crontab on Linux servers
- Setting up GitHub Actions workflow schedules using cron syntax
- Configuring AWS EventBridge or Lambda scheduled triggers
- Creating Kubernetes CronJob specifications for recurring tasks
- Scheduling data import/export jobs in ETL pipelines
- Setting up health check or monitoring pings at regular intervals
Solução de problemas
Cron job runs at unexpected times
Solução
Cron expressions use the system timezone of the server or the cloud provider's default. AWS EventBridge uses UTC, GitHub Actions uses UTC. Check and account for timezone differences when setting schedules.
Using both day-of-month and day-of-week causes unexpected behavior
Solução
When both fields are set (not *), most cron implementations run the job when either condition is met (OR logic, not AND). Use * for one of the fields if you want only the other to apply.
Expression with */5 runs at unexpected minutes
Solução
*/5 means every 5 minutes starting from 0: 0, 5, 10, 15... This is standard step syntax. If you need to start at a different offset, use a comma-separated list (e.g., 3,8,13,18).
Perguntas frequentes
What cron format is used?
Standard 5-field Unix cron format: minute (0–59), hour (0–23), day-of-month (1–31), month (1–12), day-of-week (0–7, where both 0 and 7 are Sunday). This is compatible with crontab, GitHub Actions, AWS EventBridge, and most schedulers.
What does * mean in a cron field?
* means "every valid value" for that field. For example, * in the hour field means every hour. Combined: 0 * * * * means "at minute 0 of every hour every day".
What does */ mean in a cron expression?
*/n is step syntax meaning "every n units". For example, */15 in the minute field means every 15 minutes (0, 15, 30, 45). */2 in the hour field means every 2 hours.
How do I run a cron job every 5 minutes?
Use */5 in the minute field: */5 * * * *. This runs at 0:00, 0:05, 0:10, etc. every hour every day.
Does cron support seconds?
Standard Unix crontab does not support seconds — the minimum interval is 1 minute. Some platforms like Spring Scheduler and Quartz use a 6-field format with seconds. GitHub Actions and AWS EventBridge use the standard 5-field format.
What timezone does cron use?
Standard crontab uses the local system timezone. Cloud schedulers like AWS EventBridge default to UTC. Always check and document the timezone assumption for your scheduled jobs to avoid confusion when DST changes occur.
Is my data sent to a server?
No. All cron expression generation and validation is performed locally in your browser. No data is transmitted or stored.
Can I use this for GitHub Actions?
Yes. GitHub Actions uses the standard 5-field cron syntax in the on.schedule.cron field. Note that GitHub Actions scheduled workflows run in UTC timezone.