Cron Expression Parser
Paste a standard 5-field cron expression and get an instant plain-English explanation, a field-by-field breakdown table, and the next 5 scheduled run times. Everything runs in your browser - nothing is sent to a server.
Try These Examples
0 0 * * *— Every day at midnight30 8 * * 1— Every Monday at 8:30 AM0 0 1 * *— First day of every month at midnight*/15 9-17 * * 1-5— Every 15 minutes, 9 AM–5 PM, Mon–Fri
How It Works
A standard cron expression consists of five space-separated fields that together define when a job should run. Each field can use special characters to express complex schedules in a compact format.
| Field | Allowed Values | Special Characters |
|---|---|---|
| Minute | 0–59 | * , - / |
| Hour | 0–23 | * , - / |
| Day of Month | 1–31 | * , - / |
| Month | 1–12 | * , - / |
| Day of Week | 0–6 (Sun–Sat) | * , - / |
Special character reference
*— matches every possible value for that field.,— separates a list of values, e.g.1,3,5means the 1st, 3rd, and 5th.-— defines a range, e.g.9-17means every value from 9 through 17./— defines a step, e.g.*/10means every 10th value starting from 0.
Combining characters
Characters can be combined for powerful expressions. For example, 1-30/5 in the minute field means "every 5 minutes from minute 1 through minute 30" (1, 6, 11, 16, 21, 26). A field like 1,15,28 in the day-of-month position fires on the 1st, 15th, and 28th of each month.
Frequently Asked Questions
What is a cron expression?
A cron expression is a compact string of five space-separated fields (minute, hour, day-of-month, month, day-of-week) that defines a recurring schedule. It originated in Unix-like operating systems for scheduling automated tasks (cron jobs) and is now used by CI/CD pipelines, cloud schedulers, and task queues.
What do the five fields in a cron expression mean?
The five fields are, from left to right: minute (0–59), hour (0–23), day of month (1–31), month (1–12), and day of week (0–6, where 0 is Sunday). Each field can contain a single value, a comma-separated list, a range with a hyphen, a step value with a slash, or an asterisk meaning "every".
What does */15 mean in a cron expression?
The notation */15 means "every 15th unit". In the minute field, */15 fires at minutes 0, 15, 30, and 45. You can also use a range with a step, such as 1-30/5, which fires at minutes 1, 6, 11, 16, 21, and 26.
How is a 5-field cron expression different from a 6-field one?
The standard (POSIX) cron expression has five fields: minute, hour, day-of-month, month, and day-of-week. Some systems like Quartz and Spring add a sixth "seconds" field at the beginning, and occasionally a seventh "year" field at the end. This tool supports the standard 5-field format used by crontab, GitHub Actions, and most cloud schedulers.