What does */5 * * * * mean?

In a 5-field expression it means minute 0, 5, 10, and so on, every hour, every day. The schedule fires every 5 minutes.

What is the order of the 5 fields?

Minute, hour, day of month, month, day of week. Ranges are 0-59, 0-23, 1-31, 1-12, and 0-7 where both 0 and 7 are Sunday.

What is the difference between standard cron and Quartz?

Quartz adds a seconds field and uses ? when day-of-month or day-of-week should be left unset. It also supports L, W, and #. Standard 5-field cron does not.

What timezone do GitHub Actions and Vercel Cron use?

UTC. A schedule of 0 9 * * 1-5 runs at 09:00 UTC, which is not 9am in every local timezone.

How do I run every weekday at 9am?

Use 0 9 * * 1-5. That is minute 0, hour 9, Monday through Friday. Set the timezone here to the zone you mean, and remember hosted crons stay on UTC.

How do day-of-month and day-of-week combine?

In standard cron, if both are restricted, the job runs when either matches. That is OR, not AND. Quartz avoids the ambiguity by setting one of them to ?.

Cron expression builder

Build or paste a cron schedule, read it in plain English, and see the next run times.

Runs in browser

Use via MCP

Use from your agent

Streamable HTTP at https://benchline.fabwaseem.com/mcp. No key. The tool name is explain_cron.

mcp.jsonjson

2 "mcpServers": {

3 "benchline": {

4 "url": "https://benchline.fabwaseem.com/mcp"

5 }

6 }

tools/calljson

2 "jsonrpc": "2.0",

3 "id": 1,

4 "method": "tools/call",

5 "params": {

6 "name": "explain_cron",

7 "arguments": {

8 "expression": "0 * * * *",

9 "dialect": "standard",

10 "timeZone": "UTC"

11 }

12 }

13}

Related tools

How it works

Free cron expression generator and explainer. Build a schedule visually or paste one to translate it into plain English, validate it, and preview the next 10 run times in any timezone. Supports standard 5-field cron, seconds, Quartz, and macros.

01
Pick a preset or build fields
Start from a preset or set minute, hour, day, month, and weekday. The expression stays in sync with the fields.
02
Read the English and check the next runs
The sentence and the next 10 times use the timezone you pick. Compare them with UTC before you deploy.
03
Copy for crontab, GitHub Actions, Vercel, or Kubernetes
Each snippet is ready to paste. GitHub Actions and Vercel Cron stay on UTC.