ACTIONS SCHEDULE CRON CHECK · RUNS IN YOUR BROWSER

Will your Actions schedule run when you think it will?

GitHub runs a schedule: cron in UTC, no faster than every 5 minutes, and documents that runs can be delayed or dropped at busy times, the start of every hour among them. Paste your workflow YAML below and this page lists every cron that is invalid, too frequent or on minute 0, with the one-line fix.

Nothing is uploaded. The YAML you paste is read in this browser and never leaves your device, and this tool makes no network calls of its own.

1. Paste one or more workflow files

Copy the contents of each file under .github/workflows/ you want checked. Add more blocks for more files — nothing here reads your repository, so pasting is how it sees anything.

Paste at least one workflow file above and click Check.

Prefer a CLI, or want this in your own CI?

Same logic, zero dependencies, one file:

python3 check.py                  # scan .github/workflows under the current directory
python3 check.py /path/to/repo    # scan a specific checkout
python3 check.py --format json    # machine-readable
python3 check.py --fail-on-risk   # exit 2 if any finding exists

Get check.py from the repo — stdlib only, nothing to install, no network calls. Wire --fail-on-risk into your own CI to block a bad cron before it merges.

Common questions

Why does my GitHub Actions scheduled workflow run late or not at all?

GitHub documents that scheduled workflows can be delayed, and may be dropped, during periods of high load, and names the start of every hour as a high-load time. A cron of minute 0 lands on that peak; moving to an off-peak minute such as 17 is the documented mitigation.

What is the shortest interval a GitHub Actions cron can run at?

5 minutes. An entry such as * * * * * or */1 * * * * asks for more than GitHub supports, so it cannot run as often as written.

Why is my schedule cron rejected or ignored?

GitHub cron takes exactly five fields: minute, hour, day of month, month and day of week. A six-field cron with a seconds column, or a number outside a field's range such as minute 61, is invalid.

Does this tool fetch anything from GitHub for me?

No. It makes no network calls at all. Paste your workflow YAML and the scan runs entirely in this page.

Does a clean scan mean my workflows are safe?

No. This checks one specific pattern, the cron expressions, in each file you paste. It is not a security audit and it does not tell you when a run will actually start. Cron times are UTC.

More: why scheduled workflows run late, and which minute to pick