Generate or explain five-field cron expressions locally. Build daily, weekly and monthly schedules with clear syntax checks.
Generate a schedule or explain an existing one
Choose a preset for minute steps, hourly, daily, weekdays, weekly or monthly execution. Only the relevant inputs remain enabled. For a custom schedule, select Explain existing expression and enter five fields without a command. Generate displays the expression and a readable breakdown. Copy it or download a text file. Nothing is installed on a server, and this page does not execute a job.
Read the five fields in order
The fields are minute, hour, day of month, month and day of week. Minutes range from 0 to 59, hours from 0 to 23, dates from 1 to 31 and months from 1 to 12. Weekdays use 0 to 7, with both 0 and 7 representing Sunday. The tool also accepts three-letter month and weekday names, such as JAN and MON, and normalises them into numbers.
Wildcards, lists, ranges and steps
An asterisk allows every value in that field. A list such as 1,3,5 allows those values. A range such as 1-5 covers each value between its endpoints. A step such as */15 in the minute field selects minutes 0, 15, 30 and 45. The parser also supports stepped ranges like 1-10/3. It rejects steps on a single number, reversed ranges, out-of-range values and unsupported syntax.
Examples you can adapt
30 9 * * 1-5 means 09:30 from Monday to Friday. 0 18 * * 0 means 18:00 every Sunday. 0 8 1 * * selects 08:00 on the first day of each month. A schedule for day 31 will not run in a month without that date. Keep your command separate: this tool builds only the schedule fields and never asks for shell scripts or server credentials.
Day matching and interval traps
With conventional cron, restricting both day of month and day of week uses an OR rule: either may match. For example, 30 9 1 * 1 selects the first day of the month plus Mondays at 09:30. Steps reset inside their field. */40 in minutes means minute 0 and minute 40 of each hour, not a continuous forty-minute delay between every run. These distinctions are shown in the output where relevant.
Timezone, dialect and deployment checks
Times refer to the timezone configured for your cron server; this tool does not convert timezones or predict daylight-saving behaviour. It supports five-field cron, not Quartz seconds, L, W, #, @ shortcuts or a full crontab line. Before installing a schedule, confirm your scheduler syntax, timezone, command permissions and logs. Treat the result as a schedule to review, not a guarantee that a job ran.
Advice
Keep the original input and inspect the generated result before using it in a real project.
Frequently asked questions
Does this install a cron job?
No. It generates or explains schedule text only.
Are seconds supported?
No. Enter conventional five-field cron without seconds.
Which timezone is used?
Your server scheduler determines it. This tool performs no timezone conversion.
Does */40 mean every forty elapsed minutes?
No. It matches minutes 0 and 40 within each hour.