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Cron Expression Builder
Build a five-field Unix cron expression from explicit field selections.
Minutes, Hours, Days of month, Months, Days of week (0=Sunday)
schedule.cron, cron-expression-builder.report.json
Browser only
Runs locally in your browser. Your files, pasted content and generated output are not uploaded. Reset clears this tool’s working data.
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How to use this tool
- Enter values using the examples, or choose a local file where requested. Follow the displayed supported input shapes and limits.
- Choose Calculate result and inspect the complete result.
- Download result to save the primary file. Where supplied, additional links save source files and the full JSON report. Reset restores examples and clears output.
Examples
Minutes: 0,30
Hours: 9
Days of month: *
Months: *
Days of week (0=Sunday): 1,2,3,4,5
Limitations
- Five-field Unix cron only. Each field accepts * or integer lists/ranges,with positive steps on * or a range. Minutes0–59,hours0–23,month-days1–31,months1–12,weekdays0–6. Output sorts/deduplicates explicit selections; only an unrestricted * remains *. Restricted full date sets stay numeric to preserve Unix OR semantics. No seconds,names,macros,timezone or schedule guarantee.
- Text fields are limited to100,000 UTF16 units each and400,000 combined UTF8 bytes; file fields have their own displayed limits. Combined output is at most4MiB. Processing stops after30 seconds; tool-specific bounds may be tighter.
- Generated source is a downloadable result and is not executed here. Inspection does not establish remote behavior, trust or standards certification.
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