cronbits

Cron expressions for Node.js: parse, validate, find the next/previous run times, describe schedules in plain text, and run an in-process job scheduler.

Zero runtime dependencies. Node 18+.

Install

npm install cronbits

Quick start

import { parse, next, previous, describe, createScheduler } from "cronbits";

parse("*/5 * * * *").matches(new Date()); // every 5 minutes?

next("0 9 * * 1-5", new Date());     // next weekday 09:00
previous("@hourly", new Date());     // previous hour
describe("0 0 1 * *");               // human-readable fields

const scheduler = createScheduler();
scheduler.add("reports", "0 6 * * *", async ({ at }) => {
  console.log("daily report", at.toISOString());
});
scheduler.start();

Cron syntax

Standard 5-field cron: minute hour day-of-month month day-of-week

• Lists: 1,15
• Ranges: 1-5
• Steps: */15, 1-10/2
• Names: JAN, MON
• Presets: @yearly @monthly @weekly @daily @hourly

Scheduler API

| Method | Purpose | | --- | --- | | add(name, expr, handler) | Register a job | | remove / pause / resume | Manage jobs | | start / stop | Control the timer loop | | runNow(name) | Fire immediately | | list() | Snapshot of jobs |

License

MIT