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★ Cron cheat sheet

Cron Expression: Every 5 Minutes

The most common polling schedule: 288 runs a day at :00, :05, :10 and so on. It’s also exactly the shortest interval GitHub Actions allows.

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The expression

*/5 * * * *

Every 5 minutes.

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

✓ Valid 5-field cron

Quick picks

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

In plain English

Every 5 minutes.

Next 10 runs

Paste it into your platform

Time zone: UTC

*/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 */5 * * * * means

Field by field:

Field breakdown
FieldValueMatches
Minute*/50, 5, 10, 15, 20, 25 … 55 (12 values)
Hour*any
Day of month*any
Month*any
Day of week*any
02

Gotchas

  • Runs at :00 coincide with every other scheduled job on shared platforms. On GitHub Actions, the top of the hour is the most delayed slot; 2-59/5 shifts every run off it.
  • Vercel Hobby rejects it (once per day maximum); Pro allows 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.
VercelNot supportedHobby plan: deploy fails, because Hobby cron jobs may run at most once per day. Pro and Enterprise allow once per minute.
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 expression for every 5 minutes?
*/5 * * * *. The */5 in the minute field means every minute divisible by 5, so the job runs at :00, :05, :10 … :55 of every hour.
Is 0/5 the same as */5?
In standard cron, yes. AWS EventBridge uses the 0/5 form, and the AWS tab above shows the converted expression.
Will GitHub Actions run it exactly every 5 minutes?
Not reliably. GitHub documents that scheduled runs can be delayed under load, and 5 minutes is its minimum, so expect gaps.
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.