Cron Expression Builder
Every minute
*Every minute (0-59)
*Every hour (0-23)
*Every day of month (1-31)
*Every month (1-12)
*Every day of week (0-6)
Next 5 Executions
Cron Field Reference
0-59
0-23
1-31
1-12 (1=Jan)
0-6 (0 or 7=Sun)
* any value, value list- range/ step valuesHave an expression already? Test it with our Cron Expression Tester to see next run times and convert natural language to cron.
What This Tool Does
Cron Expression Builder is built for deterministic developer and agent workflows.
Visual cron expression builder with human-readable descriptions and next execution times. Free online cron tool.
Use How to Use for execution steps and FAQ for constraints, policies, and edge cases.
Last updated:
This tool is provided as-is for convenience. Output should be verified before use in any production or critical context.
Agent Invocation
Best Path For Builders
Dedicated API endpoint
Deterministic outputs, machine-safe contracts, and production-ready examples.
Dedicated API
https://aidevhub.io/api/cron-expression/parse/ OpenAPI: https://aidevhub.io/api/openapi.yaml
Unified Runtime API
https://aidevhub.io/api/tools/run/?toolId=cron-builder&a=...
GET and POST are supported at /api/tools/run/ with identical validation and limits.
Limit: 30 req / 60s, input max 256 KB.
REST API
Base URL
https://aidevhub.io/api/cron-expression/ 50 requests/day per IP. No authentication required. CORS enabled. OpenAPI spec
Endpoints
Example
curl "https://aidevhub.io/api/cron-expression/parse/?expression=0+9+*+*+1-5"
Example Response
{
"valid": true,
"expression": "0 9 * * 1-5",
"human": "At 09:00, Monday through Friday"
} How to Use Cron Expression Builder
- 1
Pick a preset or start from scratch
Open the Presets dropdown for common schedules like every 5 minutes, daily at midnight, or weekdays at 9 AM. The expression updates instantly.
- 2
Set each field's mode
Each field (minute, hour, day, month, weekday) offers Every, Specific, Range, and Step modes. Pick values to build the exact schedule you need.
- 3
See the cron expression preview
The cron syntax (e.g., `0 9 * * 1-5` for 9 AM weekdays) and a plain-English description update in real time as you edit the fields.
- 4
Copy cron expression
Click 'Copy' to copy the expression to your clipboard. Paste into crontab, GitHub Actions, AWS CloudWatch, or any scheduler that uses cron syntax.
- 5
Check the next run times
The 'Next 5 Executions' list updates automatically with upcoming run times in local time, so you can confirm the schedule before deploying.