CronLens

Quartz cron expression builder

Quartz cron expressions have six or seven fields, starting with seconds, and add special characters such as L, W and #. Type one to see its meaning and next fire times in the time zone of your choice. It all runs in your browser.

    History and favourites (stored only in this browser)

      Nothing saved yet. Expressions you check are saved here, in your browser's local storage, never on a server.

      Runs locally. The expression is never uploaded. The share link keeps it after the # sign, which browsers never send to a server.

      How to use

      1. Write the fields in this order: seconds, minutes, hours, day-of-month, month, day-of-week and, optionally, year. The line under the box labels each field while you type.
      2. Put ? in either the day-of-month or the day-of-week field, and a real value or * in the other. If you want every day, use * ? or ? * in that position.
      3. Use the special characters where you need them: L for last, W for the nearest weekday, # for the nth weekday of the month, and L-n for n days before the last day.
      4. Select the time zone. Quartz triggers carry their own time zone (the JVM default when none is set), so choose the one your trigger uses.
      5. Compare the fire times with what you expect, then paste the expression into your CronScheduleBuilder or Spring configuration.

      Worked examples

      The third Friday of every month at 10:15

      0 15 10 ? * 6#3. Day-of-week 6 is Friday and #3 means the third such day. October 2026 starts on a Thursday, so its Fridays are the 2nd, 9th, 16th, 23rd and 30th: the third is the 16th.

      Quartz, time zone UTC, runs after 2026-10-01 00:00 UTC
      0 15 10 ? * 6#3

      1. Fri 2026-10-16 10:15:00 +00:00
      2. Fri 2026-11-20 10:15:00 +00:00
      3. Fri 2026-12-18 10:15:00 +00:00

      The last weekday of the month

      0 0 0 LW * ? fires at midnight on the last Monday-to-Friday of the month. Observe November: the 30th is a Monday, and December's 31st is a Thursday.

      Quartz, time zone UTC, runs after 2026-10-01 00:00 UTC
      0 0 0 LW * ?

      1. Fri 2026-10-30 00:00:00 +00:00
      2. Mon 2026-11-30 00:00:00 +00:00
      3. Thu 2026-12-31 00:00:00 +00:00

      The fifth Thursday, which only some months have

      0 0 0 ? * 5#5 fires only in months that have five Thursdays. After October and December 2026 the next such month is April 2027.

      Quartz, time zone UTC, runs after 2026-10-01 00:00 UTC
      0 0 0 ? * 5#5

      1. Thu 2026-10-29 00:00:00 +00:00
      2. Thu 2026-12-31 00:00:00 +00:00
      3. Thu 2027-04-29 00:00:00 +00:00

      Every 20 seconds

      */20 * * * * ? shows what the leading seconds field is for: fires at :00, :20 and :40 of every minute.

      Quartz, time zone UTC, runs after 2026-10-01 00:00 UTC
      */20 * * * * ?

      1. Thu 2026-10-01 00:00:20 +00:00
      2. Thu 2026-10-01 00:00:40 +00:00
      3. Thu 2026-10-01 00:01:00 +00:00

      Daily at 02:30 across the spring clock change

      In New York 02:30 does not exist on 8 March 2026. The Quartz tutorial warns that DST can "skip or repeat" a firing, and with Quartz 2.3.2 on JDK 17 the skipped day is simply left out:

      Quartz, time zone America/New_York, runs after 2026-03-07 12:00 UTC
      0 30 2 * * ?

      1. Mon 2026-03-09 02:30:00 -04:00
      2. Tue 2026-03-10 02:30:00 -04:00
      3. Wed 2026-03-11 02:30:00 -04:00

      Limits & gotchas

      • Daylight saving is observed, not documented. The tutorial only says a change "can cause a skip or a repeat". The spring-forward skip and the single fire in the repeated hour (at the second occurrence) were observed on Quartz 2.3.2 with JDK 17 only. See the calculator page for the comparison with other schedulers.
      • Quartz 2.3.2 is the reference. The engine was compared with the real Quartz jar on randomly generated expressions with no differences, except that nW (nearest weekday) for days after the 28th behaves inconsistently in short months in Quartz itself, so the tool warns and does not list those months.
      • The documentation has gaps and conflicts. The year range differs between the tutorial and the javadoc, the javadoc month table says 0-11 while the tutorial and Quartz's actual behaviour use 1-12, and combining L with lists in day-of-week gives results the javadoc calls confusing. A # expression must be the only item in the day-of-week field.
      • Ranges can wrap. The javadoc says a range such as 22-2 works, and that 7/6 in the month field turns on only month 7.
      • Other Java schedulers differ. Spring's @Scheduled(cron=...) is a different parser with its own rules. This page models Quartz only.

      FAQ

      Why does Quartz insist on a question mark?

      Quartz cannot combine a day-of-month restriction and a day-of-week restriction, so exactly one of those two fields must be ? ("no specific value"). The Quartz tutorial says specifying both is not currently supported. Classic Linux cron resolves the same situation with an OR rule instead.

      Is Sunday 0 or 1 in Quartz?

      In Quartz the day-of-week field runs from 1 to 7 with 1 as SUN, so 6 is Friday. Linux cron uses 0 or 7 for Sunday. That is why "6#3" means the third Friday in Quartz. Names such as SUN and FRI avoid the confusion and Quartz accepts them in any letter case.

      What does 0 0 0 LW * ? do?

      LW means the last weekday of the month. In October 2026, the 31st is a Saturday, so the last weekday is Friday the 30th. The tool lists the next dates so you can confirm this for your own month.

      What happens with 5#5 when a month has no fifth Thursday?

      The Quartz tutorial says that for a #5 expression, if the month has no fifth occurrence of that weekday, no trigger fires that month. In 2026 the fifth Thursday occurs on 29 October and 31 December, and the tool skips the months in between.

      Does the optional year field work as expected?

      Yes, as an optional seventh field. The tutorial gives the range as 1970-2099 but the CronExpression javadoc says 1970-2199, so the two official documents disagree; this tool accepts the wider range and does not warn about it. Keep your year inside the narrower, tutorial range if you need to be safe.

      Sources

      Every document above was opened and read on 2026-10-01. Documentation changes; if a page here disagrees with the current docs, trust the docs and tell us.