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★ Cron cheat sheet

Cron Expression: Every Weekday

Monday to Friday at midnight. Swap the minute and hour for the time you want.

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The expression

0 0 * * 1-5

At 00:00 on Monday through Friday.

  1. 0Minute
  2. 0Hour
  3. *Day of month
  4. *Month
  5. 1-5Day of week

✓ Valid 5-field cron

Quick picks

Typing by hand. Pick a pattern above to build one with inputs instead.

In plain English

At 00:00 on Monday through Friday.

Next 10 runs

Paste it into your platform

Time zone: UTC

0 0 * * 1-5 /usr/local/bin/my-job >> /var/log/my-job.log 2>&1
  • OKRuns in the server’s local time zone. cronie (RHEL, Fedora) accepts a CRON_TZ= line above the job; Debian’s cron does not.
  • Heads-upEscape % as \% in the command: an unescaped % ends the command and starts stdin.
  • Heads-upcron runs with a minimal PATH and no login shell. Use absolute paths and redirect output, or failures disappear.
  • Linux crontab docs ↗

Cron jobs failing silently?

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01

What 0 0 * * 1-5 means

Field by field:

Field breakdown
FieldValueMatches
Minute00
Hour00
Day of month*any
Month*any
Day of week1-5Monday, Tuesday, Wednesday, Thursday, Friday
02

Gotchas

  • Day-of-week 1-5 is Monday to Friday in standard cron (Sunday is 0 or 7). AWS numbers days 1-7 from Sunday, so the AWS tab converts it to 2-6.
  • Midnight Monday UTC is still Sunday evening in the Americas.
03

Does it run everywhere?

Checked against each platform's rules, assuming UTC:

Platform support
PlatformVerdictWhy
Linux crontabWorks, with a catchEscape % as \% in the command: an unescaped % ends the command and starts stdin.
GitHub ActionsWorks, with a catchRuns at minute 0 are the most likely to be delayed or dropped under load. GitHub suggests another minute, e.g. 17.
VercelWorks, with a catchVercel now labels Cron Jobs “legacy” in favour of Vercel Schedules, which add time zones. Existing crons keep working.
AWS EventBridgeWorksSix fields: the year is added at the end, and one of day-of-month / day-of-week must be ?.
KubernetesWorks, with a catchWithout timeZone, the schedule uses the kube-controller-manager’s local zone. TZ= or CRON_TZ= inside schedule is rejected from v1.29.
04

Questions engineers actually ask

What is the cron for weekdays only?
Put 1-5 in the day-of-week field: 0 0 * * 1-5. MON-FRI works too, except on Vercel, which only accepts numbers.
How do I skip public holidays?
Cron has no calendar awareness. Check for holidays inside the job and exit early.
Why does my job run on days I didn't expect?
Probably the day-of-month / day-of-week OR rule. If both fields are set, cron runs when either matches. Set one of them to * to get the usual AND behaviour.
What time zone does cron use?
Whatever the scheduler uses: the server's zone for Linux cron, UTC for Vercel and EventBridge rules, UTC by default on GitHub Actions (with an optional timezone key) and the controller's zone on Kubernetes unless spec.timeZone is set.
05

Other schedules

06

More from the workbench

Fine print

Tools: on the house.
Engineer: by the hour.

Infra that doesn't page you at 3am costs a little more. I build background job systems with retries, alerting and dashboards.

I'm Himanshu, an AI and full-stack engineer. I build MVPs, AI agents and the growth plumbing around them for early-stage startups.