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Developers and DevOps engineers frequently copy-paste cron expressions from docs or colleagues without a quick way to verify ...

The problem

Developers and DevOps engineers frequently copy-paste cron expressions from docs or colleagues without a quick way to verify what they actually do — you have to either memorize the 5-field format or open a third-party web tool.

If you've hit this before, you know how it goes — you open a cron decoder website, paste in the expression, and squint at the output. Or you open a man page.

As a solution, I created cron-human

Translate a cron expression into plain English and print the next 5 scheduled run times

It's zero-dependency Node.js, so you can run it immediately without installing anything:

npx cron-human "0 3 * * 1-5"
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Output:

$ npx cron-human "0 3 * * 1-5"

Expression:  0 3 * * 1-5
Meaning:     at 03:00, Monday through Friday
Timezone:    UTC

Next 5 runs:
  1  2026-05-18 Mon  03:00 UTC  (in ~17h)
  2  2026-05-19 Tue  03:00 UTC  (in ~1d 17h)
  3  2026-05-20 Wed  03:00 UTC  (in ~2d 17h)
  4  2026-05-21 Thu  03:00 UTC  (in ~3d 17h)
  5  2026-05-22 Fri  03:00 UTC  (in ~4d 17h)
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How it works

Pure Node.js cron parser: splits the expression into 5 fields (minute, hour, day-of-month, month, day-of-week), evaluates each field including ranges, lists, and steps, then walks forward from the current UTC time to find the next 5 matching timestamps. No network calls, no dependencies.

Why I built it

Found repeated questions on r/devops and r/sysadmin asking 'what does this cron mean?' and 'when will this next run?'. Existing solutions are either web tools requiring a browser round-trip with no pipe/stdin support, or npm libraries like cronstrue that require installation and provide no next-run dates. A zero-dep CLI that runs instantly with npx fills this gap cleanly for the terminal workflow.

Try it

npx cron-human --help
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Part of µ micro — one new developer CLI tool, shipped every day. All tools are zero-dependency Node.js and run instantly with npx.

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