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Cron Expression Parser

Parse 5-field Unix cron and 6-field cron expressions with seconds, then show field meanings, upcoming run times, and risk hints.

Cron expression

Enter an expression to parse it locally. Supports Unix 5-field cron and 6-field cron with seconds.

Unix 5-field

Format: minute hour day month weekday; with seconds: second minute hour day month weekday. Quartz ? is treated as a wildcard.

Runs to show
Timezone
Target runtime

Field breakdown

5 fields
Minute
*/5
Every 5 units
Hour
*
Any value
Day
*
Any value
Month
*
Any value
Weekday
*
Any value

Visual builder

Generate an expression from common scheduling patterns, then copy or apply it.

Unix 5-field
Runs daily at 09:00.
0 9 * * *

Test cases

Load common, platform-specific, and edge-case expressions to inspect previews and diagnostics.

9
Recommended
Platform differences
Edge cases
Format
Unix 5-field
Timezone
Local timezone (Browser local timezone)
Runs
-
Target runtime
Auto detect
Base time
-

Readable explanation

Runs every 5 minutes.

Upcoming run times

Calculated from the current time and selected timezone.

Local timezone (Browser local timezone)
Upcoming run times will appear here after you enter a valid expression.

Recent parses

Automatically keeps recent valid cron combinations.

Valid expressions will appear here automatically.

Favorite expressions

Save common jobs and restore them in one click.

0
No favorite expressions yet.

Diagnostic snapshot

Package the current parse result as Markdown or JSON for sharing, archiving, and debugging.

Includes diagnostics

Markdown snapshot

Best for issues, docs, and operations notes.

# Cron Expression Parser

- Expression: `*/5 * * * *`
- Valid: No
- Format: Unix 5-field
- Target runtime: Auto detect
- Timezone: Local timezone (Browser local timezone)
- Generated at: -

## Readable

Runs every 5 minutes.

## Field breakdown

| Field | Value | Hint |
| --- | --- | --- |
| Minute | `*/5` | Every 5 units |
| Hour | `*` | Any value |
| Day | `*` | Any value |
| Month | `*` | Any value |
| Weekday | `*` | Any value |

## Upcoming run times

| # | Local time | ISO |
| --- | --- | --- |
| - | - | - |

## Diagnostics

- **info** Waiting for expression: Enter a cron expression to start parsing.

JSON snapshot

Best for logs, tickets, or automation workflows.

{
  "tool": "Cron Expression Parser",
  "generatedAt": null,
  "baseTime": null,
  "expression": "*/5 * * * *",
  "valid": false,
  "format": "Unix 5-field",
  "scheduler": {
    "value": "auto",
    "label": "Auto detect"
  },
  "timezone": {
    "value": "local",
    "label": "Local timezone (Browser local timezone)",
    "resolved": null
  },
  "readable": "Runs every 5 minutes.",
  "fields": [
    {
      "key": "minute",
      "label": "Minute",
      "value": "*/5",
      "hint": "Every 5 units"
    },
    {
      "key": "hour",
      "label": "Hour",
      "value": "*",
      "hint": "Any value"
    },
    {
      "key": "dayOfMonth",
      "label": "Day",
      "value": "*",
      "hint": "Any value"
    },
    {
      "key": "month",
      "label": "Month",
      "value": "*",
      "hint": "Any value"
    },
    {
      "key": "dayOfWeek",
      "label": "Weekday",
      "value": "*",
      "hint": "Any value"
    }
  ],
  "nextRuns": [],
  "diagnostics": [
    {
      "severity": "info",
      "title": "Waiting for expression",
      "detail": "Enter a cron expression to start parsing."
    }
  ]
}

Diagnostics

Needs check

Waiting for expression

Info

Enter a cron expression to start parsing.

Capabilities

Preview upcoming runs
Readable explanation
Frequency and compatibility hints
Common schedule examples

About Cron Expression Parser

Explain schedules and preview upcoming runs. Parse 5-field Unix cron and 6-field cron expressions with seconds, then show field meanings, upcoming run times, and risk hints. The core workflow is designed to run in your current browser.

Key capabilities

  • Preview upcoming runs
  • Readable explanation
  • Frequency and compatibility hints
  • Common schedule examples

Useful for

  • Verify server scheduled jobs before shipping
  • Spot overly frequent jobs or date-rule ambiguity
  • Prepare expressions for CI, monitoring, and sync jobs

Frequently asked questions

Is Cron Expression Parser free to use online?

Yes. Cron Expression Parser opens in a modern browser and does not require desktop software installation.

What is Cron Expression Parser useful for?

Common use cases include Verify server scheduled jobs before shipping; Spot overly frequent jobs or date-rule ambiguity.

Is my input or file uploaded?

The core processing workflow is designed to run locally in the browser. Key capabilities include Preview upcoming runs, Readable explanation, Frequency and compatibility hints; account, comments, and anonymous analytics may still create normal site requests.

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