Build cronjobs or list next dates

"CronMaker is a utility which helps you to build cron expressions." Check it out at http://www.cronmaker.com/ Show archive.org snapshot .

To simply check syntax of a cron schedule, paste it into your personal crontab file using crontab -e. If you have syntax errors, the crontab command will complain like this:

crontab: installing new crontab
"/tmp/crontab.3szkFA/crontab":0: bad minute
errors in crontab file, can't install.
Do you want to retry the same edit? (y/n) y