Does node-cron use the system crontab?

No. node-cron runs entirely within your Node.js process using JavaScript timers. Your system crontab is not involved.

What happens to cron jobs when my Node.js app restarts?

In-process cron jobs are lost when the process stops. They resume when the process starts again since schedules are defined in code. Any in-flight task is interrupted.

Can I use 6-field cron expressions with seconds?

Yes. node-cron supports an optional seconds field as the first field. For example, `*/30 * * * * *` runs every 30 seconds.

How do I handle timezones with node-cron?

Pass a `timezone` option: `cron.schedule(expression, callback, { timezone: "America/New_York" })`. Uses IANA timezone names.

Should I use node-cron or the cron package?

node-cron is simpler with no external dependencies. The cron package offers more features like nextDate() and a class-based API. For most use cases, node-cron is sufficient.

beginner 10 min read

How to Set Up Cron Jobs in Node.js (Complete Guide)

Learn how to schedule cron jobs in Node.js using node-cron and other libraries. Includes code examples, error handling, PM2 setup, and production tips.

Prerequisites

Node.js 18+
npm or yarn
Basic understanding of cron syntax

Cron Jobs in Node.js

Unlike system cron, Node.js cron jobs run inside your application process. This means they have access to your app's context — database connections, environment variables, and modules — without spawning separate processes.

The most popular library is node-cron, which provides a simple API for scheduling tasks using standard cron expressions.

Quick Start with node-cron

Install node-cron:

bash

npm install node-cron

Schedule a task:

javascript

import cron from 'node-cron';

cron.schedule('*/5 * * * *', () => {
  console.log('Running task every 5 minutes');
});

cron.schedule('0 9 * * *', () => {
  console.log('Good morning! Running daily task.');
});

That's it. The tasks run as long as your Node.js process is alive.

node-cron API Deep Dive

Scheduling with options:

javascript

const task = cron.schedule('0 * * * *', () => {
  console.log('Hourly task');
}, {
  scheduled: false,
  timezone: 'America/New_York',
});

task.start();
task.stop();

Validating expressions:

javascript

cron.validate('*/5 * * * *');  // true
cron.validate('invalid');       // false

Using seconds (6-field expressions):

javascript

// Run every 30 seconds
cron.schedule('*/30 * * * * *', () => {
  console.log('Every 30 seconds');
});

Alternative: The cron Package

The cron package offers a class-based API with more control:

bash

npm install cron

javascript

import { CronJob } from 'cron';

const job = new CronJob(
  '0 */2 * * *',
  function () {
    console.log('Running job');
  },
  null,
  true,
  'America/Los_Angeles'
);

job.stop();
job.start();
console.log(job.nextDate());

The cron package uses Luxon for date handling since v2.

Common Cron Expressions

Expressions you'll use most often:

* * * * * — Every minute
*/5 * * * * — Every 5 minutes
0 * * * * — Every hour
0 0 * * * — Daily at midnight
0 9 * * 1-5 — Weekdays at 9 AM
0 0 1 * * — First day of every month
0 0 * * 0 — Every Sunday at midnight

Try it Open in full editor

Every weekday at 9:00 AM

Next runs (UTC):

Mon, May 18, 2026 09:00

Tue, May 19, 2026 09:00

Wed, May 20, 2026 09:00

Error Handling & Logging

Always wrap your cron callbacks in try/catch. An uncaught exception can crash your process:

javascript

cron.schedule('0 * * * *', async () => {
  try {
    await processData();
    console.log('[cron] processData completed');
  } catch (error) {
    console.error('[cron] processData failed:', error);
  }
});

Preventing overlapping runs:

javascript

let isRunning = false;

cron.schedule('*/5 * * * *', async () => {
  if (isRunning) return;
  isRunning = true;
  try {
    await longRunningTask();
  } finally {
    isRunning = false;
  }
});

Production: PM2 and systemd

In production, you need your Node.js process to stay alive:

PM2 (recommended):

bash

npm install -g pm2
pm2 start app.js --name "my-app"
pm2 save
pm2 startup

systemd service:

ini

[Unit]
Description=My Node App
After=network.target

[Service]
Type=simple
User=node
WorkingDirectory=/opt/my-app
ExecStart=/usr/bin/node app.js
Restart=on-failure
RestartSec=10

[Install]
WantedBy=multi-user.target

Important: Node.js cron jobs run in-process. If your process restarts, any in-flight task is killed. For critical jobs, consider BullMQ or Agenda for database-backed scheduling.

Testing Cron Jobs

Separate your schedule from your task logic:

javascript

// tasks/cleanup.js
export async function cleanup() {
  const deleted = await db.deleteOldRecords(30);
  return { deleted };
}

javascript

// cron.js
import cron from 'node-cron';
import { cleanup } from './tasks/cleanup.js';

cron.schedule('0 2 * * *', cleanup);

javascript

// tasks/cleanup.test.js
test('cleanup deletes old records', async () => {
  const result = await cleanup();
  expect(result.deleted).toBeGreaterThanOrEqual(0);
});