What Cron Studio does
Explain any cron expression in plain English, see its next runs in your time zone, and copy it for crontab, Kubernetes, GitHub Actions, AWS or systemd.
Cron syntax is easy to write and easy to get wrong. A job set for 0 0 31 2 * never runs, 0 0 13 * 5 runs on the 13th and on every Friday, and a % in a command quietly breaks it. Cron Studio shows what an expression really does before you deploy it: a plain-English sentence, the next run times in the time zone you choose, and an error that points at the field you mistyped.
The same schedule is written differently almost everywhere: five fields in crontab, Kubernetes and GitHub Actions, a seconds field and question marks in Quartz and Spring, a sixth year field in AWS EventBridge, and OnCalendar in systemd. Edit it once and copy the form you need, with the platform gotchas that matter (GitHub runs in UTC, EventBridge needs a ? in one day field).
The free tool does all of this and audits the first three lines of a crontab. Pro is $19 once: audit every line, see the 24-hour load chart, and catch jobs that all start at the same minute.
Popular uses
Each opens Cron Studio already set up for that job, with steps and answers for that case.
Free vs Pro
| Feature | Free $0 · no account |
Pro |
|---|---|---|
| Plain-English explanation of unix, Quartz/Spring and AWS EventBridge expressions | Included | Included |
| Next 5, 10 or 20 run times in any time zone, with daylight-saving handled | Included | Included |
| Edit the five (or six, seven) fields one by one or paste a whole expression | Included | Included |
| Copy-ready output for crontab, Kubernetes CronJob, GitHub Actions, Quartz, AWS EventBridge, Terraform and systemd | Included | Included |
| Audit the first 3 jobs of a pasted crontab for real bugs | Included | Included |
| Audit a whole crontab, every line | — | Pro |
| 24-hour load chart and "all jobs start at minute 0" detection | — | Pro |
| Findings for unescaped %, missing PATH, lost output, overlapping runs and daylight-saving hours | — | Pro |
Pro is $19, paid once. Checkout and the licence key are handled by Dodo Payments (merchant of record). By buying you agree to the Terms and Privacy Policy.
Questions
Is Cron Studio free?
Yes, with no account and no install. The free plan includes: Plain-English explanation of unix, Quartz/Spring and AWS EventBridge expressions; Next 5, 10 or 20 run times in any time zone, with daylight-saving handled; Edit the five (or six, seven) fields one by one or paste a whole expression; Copy-ready output for crontab, Kubernetes CronJob, GitHub Actions, Quartz, AWS EventBridge, Terraform and systemd; and 1 more. Pro ($19, paid once) adds: Audit a whole crontab, every line; 24-hour load chart and "all jobs start at minute 0" detection; Findings for unescaped %, missing PATH, lost output, overlapping runs and daylight-saving hours.
Does Cron Studio upload my data?
No. Expressions and pasted crontabs are processed in your browser and are not sent to us. We only measure which buttons are used, never what you type. See the Privacy Policy for retention and deletion.
Do I need to install anything?
No. Open the page and start working. It works on desktop and mobile browsers.
How does the Pro licence work?
You pay once and receive a licence key by email from Dodo Payments (our merchant of record). Paste it under "Have a key?" inside the tool. One key works on up to 3 browsers; you can release a browser at any time to use the key elsewhere.
What does the asterisk slash number mean in cron?
*/5 in the minute field means every 5th minute of the clock: 0, 5, 10 and so on. It is not "5 minutes after the last run", so a job that takes 7 minutes will overlap itself. Use flock or a lock file if runs must not overlap.
Why does my cron job run at the wrong time?
Cron uses the time zone of the machine or container it runs on, which is often UTC. GitHub Actions and most hosted schedulers are always UTC. Pick your zone in Cron Studio to see the real local times, and convert the hours before you paste.
