Cron Builder

Cron expressions are easy to get wrong and hard to debug when they are. Cron Builder converts natural language schedules to correct cron expressions, validates existing ones, and flags the gotchas that cause production incidents.

What it does

• English → Cron: 'Every weekday at 9am' → 0 9 * * 1-5
• Cron → English: Explain any expression in plain language
• Validation: Check for invalid fields, expressions that never fire, edge cases
• Next fire times: Given an expression, list the next 5 times it fires

Common gotchas it catches

• Day-of-month AND day-of-week are OR logic (not AND) in most implementations
• DST transitions causing jobs to skip or double-fire
• Expressions that look valid but never fire
• Timezone mismatches between server time and intended schedule

No setup. No dependencies. Works with standard 5-field cron.