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★ Cron cheat sheet

Cron Expression: Every Weekend

Saturday and Sunday at midnight. Common for heavy batch jobs that should avoid weekday traffic.

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The expression

0 0 * * 6,0

At 00:00 on Saturday and Sunday.

  1. 0Minute
  2. 0Hour
  3. *Day of month
  4. *Month
  5. 6,0Day 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 Saturday and Sunday.

Next 10 runs

Paste it into your platform

Time zone: UTC

0 0 * * 6,0 /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?

I build background job systems with retries, alerting and dashboards, so you hear about failures before your customers do.

Make my jobs reliable
01

What 0 0 * * 6,0 means

Field by field:

Field breakdown
FieldValueMatches
Minute00
Hour00
Day of month*any
Month*any
Day of week6,0Sunday, Saturday
02

Gotchas

  • 6,0 lists Saturday then Sunday; 0,6 and SAT,SUN mean the same. 6-7 also works in Vixie cron, since 7 is Sunday.
  • AWS uses 7 and 1 for Saturday and Sunday, so the AWS tab converts it.
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 weekends only?
0 0 * * 6,0 runs at midnight on Saturday and Sunday.
Why not 6-0?
Ranges must go from low to high. Use a list (6,0) or 6-7 where 7 means Sunday.
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.