Cron Schedule Lint for crontab, Kubernetes CronJob, GitHub Actions, Spring and EventBridge

It reads the crontab, Kubernetes CronJob, GitHub Actions workflow, Spring annotation, wrangler.toml or systemd timer you have open and, for every schedule line, prints the next three instants it really fires at, how many times it fires in a year, and the exact dates when that wall-clock time does not exist or happens twice. Twenty-nine rules ship with it.

Backend, platform and SRE engineers who own the schedules nobody watches: the monthly invoice run, the nightly rollup, the export a finance team waits for. It is aimed at the person reviewing a schedule an assistant generated, who will be asked three weeks later why November's invoices never went out.

Because a syntax explainer holds no calendar and no time zone. It cannot tell you that 0 0 31 * * skips five months of every year, that 01:30 in America/New_York happens twice on 2026-11-01, or that 02:30 in Pacific/Auckland does not exist at all on 2026-09-27. Those answers need the time zone database, not a parser.

Checking the file you have open is free and complete: all twenty-nine rules run, every schedule gets its real run times and its transition dates, and nothing is hidden, watermarked or time-limited. The licence covers a different job - every schedule in the repository merged into one calendar, a CSV, JSON or HTML export, and machine output a CI step can fail on.

The extension is 29 US dollars once, with a 7-day full refund. Healthchecks.io Business, the ordinary cron monitor, is $20 every month for 100 jobs, which is $240 a year, forever - and by design it can only alert you after a run was already missed. This one answers before the schedule ships.