Cron expression for every 2 hours

Field breakdown

Next runs

How this schedule works

Cron evaluates the five fields of 0 */2 * * * — minute, hour, day of month, month, day of week — against the clock once a minute and starts the job on any minute where all five match, which cronstrue reads as "On the hour, every 2 hours": 12 runs per day. The runs land at 00:00, 02:00, 04:00, 06:00, 08:00, 10:00, 12:00, 14:00, 16:00, 18:00, 20:00, 22:00. Twenty-four divides by 2 without a remainder, so the spacing survives midnight: the gap from the 22:00 run to the next day's 00:00 run is the same 2 hours as every other gap.

When to use every 2 hours

Two-hourly runs fit medium-weight ETL, regenerating a static feed or sitemap, and checking an upstream source that only changes a few times a day. Twelve runs give each invocation a wide window, so a job that occasionally takes twenty minutes is in no danger of colliding with the next. Pick this cadence when hourly is more often than the data actually changes and the extra runs are pure cost. The runs land on even hours, which is worth knowing if you also keep a nightly maintenance window at an odd hour.

Common mistakes with every 2 hours

The expected mistake is 0 2 * * *, which is not "every two hours" but "once a day at 02:00" — a twelvefold reduction in runs that looks like a single missing character. The subtler one is expecting the step to be relative. It counts from hour 0, so the runs are locked to even hours no matter when you deploy, and if your maintenance window sits on an even hour this schedule walks straight into it. Because 2 divides 24 cleanly, nothing here warns you that a step which does not divide 24, such as */5, silently shortens the gap across midnight.

Platform snippets

The same expression, ready to paste into the four schedulers that read five-field cron. The notes below each snippet are the ones that follow from this schedule; the cron expression generator lists every caveat for every platform.

name: Scheduled workflow
on:
  schedule:
    - cron: '0 */2 * * *'
  workflow_dispatch:

jobs:
  scheduled:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - name: Run job
        run: echo "Running scheduled job"

apiVersion: batch/v1
kind: CronJob
metadata:
  name: my-cron-job
spec:
  schedule: "0 */2 * * *"
  jobTemplate:
    spec:
      template:
        spec:
          containers:
            - name: job
              image: my-image:latest
              command: ["/bin/sh", "-c", "echo Running"]
          restartPolicy: OnFailure

{
  "$schema": "https://openapi.vercel.sh/vercel.json",
  "crons": [
    {
      "path": "/api/cron",
      "schedule": "0 */2 * * *"
    }
  ]
}

# Edit your crontab: crontab -e
0 */2 * * * /path/to/command

# With logging:
0 */2 * * * /path/to/command >> /var/log/cron.log 2>&1

Variations

• 0 */3 * * * On the hour, every 3 hours Eight runs a day instead of twelve. Three also divides 24, so the gap survives midnight just as cleanly.
• 0 */4 * * * On the hour, every 4 hours Six runs a day. The point at which a poll starts behaving like a batch, with room for a run to take tens of minutes.
• 0 0,2,4,6,8,10,12,14,16,18,20,22 * * * At 12:00 AM, 02:00 AM, 04:00 AM, 06:00 AM, 08:00 AM, 10:00 AM, 12:00 PM, 02:00 PM, 04:00 PM, 06:00 PM, 08:00 PM and 10:00 PM The identical schedule as a list. Unwieldy at twelve values, which is exactly the case the step form exists for.
• 30 */2 * * * At 30 minutes past the hour, every 2 hours The same even hours, shifted to half past. Costs nothing and keeps the job out of the top-of-hour rush on a shared host.