Quartz cron expressions: seconds-first scheduling for Java

Quartz is the de-facto job scheduler of the Java world, embedded in countless Spring, Jenkins-adjacent and enterprise applications. Its cron syntax is a superset of the Unix one — with a seconds field in front, an optional year at the end, and stricter day-field rules. If you have ever pasted 0 0/5 * * * ? into a crontab and been rejected, this page explains why. For standard 5-field cron, our interactive generator does the work for you.

The seven fields

Position	Field	Values	Special characters
1	Seconds	0–59	`, - * /`
2	Minutes	0–59	`, - * /`
3	Hours	0–23	`, - * /`
4	Day of month	1–31	`, - * / ? L W`
5	Month	1–12 or JAN–DEC	`, - * /`
6	Day of week	1–7 or SUN–SAT (1 = Sunday)	`, - * / ? L #`
7	Year (optional)	e.g. 2026, ranges	`, - * /`

Six fields are the minimum; the year is optional, so both 0 0 12 * * ? and 0 0 12 * * ? 2026 are valid. The leading seconds field means every Unix-style position is shifted one to the right — mechanical, but easy to fumble when converting by eye.

Reading some real Quartz schedules

Expression	Meaning
`0 0/5 * * * ?`	Every 5 minutes (at second 0)
`0 0 * * * ?`	Every hour on the hour
`0 0 0 * * ?`	Every day at midnight
`0 15 10 ? * MON-FRI`	10:15 on weekdays
`0 0 12 1 * ?`	Noon on the 1st of every month
`0 0 9 ? * MON#2`	09:00 on the second Monday of the month
`0 30 8 L * ?`	08:30 on the last day of the month
`/10 * * * ?`	Every 10 seconds — impossible in crontab

The `?` requirement

Like AWS (which borrowed the convention from Quartz), you cannot constrain day-of-month and day-of-week at the same time: exactly one of the two must be ?. This is why every generic Quartz example ends in ? — the day-of-week slot is being explicitly vacated. Quartz also brings L (last day / last weekday-of-month, e.g. 6L = last Friday), W (nearest weekday to a date) and # (nth weekday, e.g. MON#2), none of which exist in 5-field cron.

Sunday = 1, and the Spring lookalike

Quartz counts weekdays 1–7 starting at Sunday, so Unix 1-5 (Mon–Fri) is Quartz 2-6. Beware the lookalike: Spring Framework’s @Scheduled(cron = ...) also takes a seconds-first 6-field string, but it follows Unix weekday numbering and happily accepts * in both day fields. An expression copied between a Quartz job store and a Spring annotation can silently change meaning — always re-check the weekday numbers when moving between the two.

Converting Quartz → Unix cron

Confirm the seconds field is 0 (anything else has no crontab equivalent).
Delete the seconds field and the year field.
Replace ? with *.
Shift numeric weekdays down by one (2-6 → 1-5), or keep names like MON-FRI.
If the expression uses L, W or #, stop — move that logic into the script.

So 0 15 10 ? * MON-FRI becomes 15 10 * * MON-FRI, which you can paste into the generator to verify: “At 10:15, Monday through Friday.”

FAQ

How many fields does a Quartz cron expression have?

Six or seven: seconds, minutes, hours, day-of-month, month, day-of-week, plus an optional year. The seconds field comes first, which is the quickest way to recognise a Quartz expression.

Why does Quartz require a ? in the day fields?

Quartz does not support specifying both day-of-month and day-of-week; exactly one of them must be ? ("no specific value"). Writing * in both is rejected as ambiguous by validators, so 0 0 12 * * ? is the canonical "every day at noon".

What number is Sunday in Quartz?

Quartz numbers day-of-week 1-7 with 1 = Sunday, like AWS and unlike Unix cron (where Sunday is 0 or 7). SAT is 7. Using names (SUN, MON …) avoids off-by-one bugs when porting.

Is Spring’s @Scheduled cron the same as Quartz?

No, and this catches many Java developers. Spring Framework has its own 6-field, seconds-first format that looks like Quartz but follows Unix weekday numbering (0-7 with both 0 and 7 = Sunday) and does not require ?. An expression can be valid in one and invalid in the other.

How do I convert a Quartz expression to standard cron?

Drop the seconds field (Quartz below one-minute precision cannot be expressed in crontab), drop the year if present, replace ? with *, and renumber weekdays down by one (Quartz 2-6 = Unix 1-5). L, W and # schedules have no 5-field equivalent and need a script-side check.