Heroku Cron Jobs: Heroku Scheduler, Cron To Go & Alternatives

Heroku Scheduler (Free but Unreliable)

Heroku Scheduler is a free add-on that runs one-off dynos on a fixed schedule. It is the most popular option because it costs nothing to install and takes seconds to set up. However, its limitations are significant.

Setup

# Install the add-on
heroku addons:create scheduler:standard

# Open the scheduler dashboard
heroku addons:open scheduler

In the dashboard, you add jobs with a command and select one of three fixed intervals: every 10 minutes, every hour, or every day at a specific time (UTC).

Example Commands

# Node.js
node scripts/cleanup-expired-sessions.js

# Python
python manage.py send_digest_emails

# Ruby
rake db:cleanup_old_records

# PHP
php artisan schedule:run

Key Limitations

• •Only 3 intervals: every 10 minutes, hourly, or daily
• •No standard cron expression syntax
• •Best-effort execution — jobs can be silently skipped
• •UTC only — no timezone configuration
• •No execution history, logs, or monitoring
• •No failure notifications

Cron To Go (Paid, More Features)

Cron To Go is a third-party Heroku add-on that provides proper cron functionality. It supports full cron expression syntax, timezone configuration, execution logs, and failure notifications.

Setup

# Install Cron To Go
heroku addons:create crontogo:bronze

# Open the dashboard
heroku addons:open crontogo

Features

• •Full cron expression syntax (1-minute granularity)
• •Timezone support (any IANA timezone)
• •Execution logs with stdout/stderr capture
• •Failure notifications via email and webhooks
• •Retry policies on failure
• •Job grouping and tagging

Pricing

Plans start at $7/month (Bronze: 5 jobs, 100 executions/day) and go up to $249/month (Platinum: unlimited jobs and executions). You still pay for the dyno time each execution uses. For teams with many scheduled tasks, costs can add up.

Custom Worker Dyno Approach

Instead of using an add-on, you can run a dedicated worker dyno that handles scheduling internally. This gives you full control but costs a full dyno 24/7.

Node.js Example with node-cron

// worker.js
const cron = require('node-cron');

// Run cleanup every hour
cron.schedule('0 * * * *', async () => {
  console.log('Running hourly cleanup...');
  try {
    await cleanupExpiredSessions();
    console.log('Cleanup completed');
  } catch (err) {
    console.error('Cleanup failed:', err.message);
  }
});

// Run report every day at 9 AM UTC
cron.schedule('0 9 * * *', async () => {
  console.log('Generating daily report...');
  await generateDailyReport();
});

console.log('Worker started, waiting for scheduled tasks...');

Procfile

web: node server.js
worker: node worker.js

# Scale up the worker dyno
heroku ps:scale worker=1

Using CronJobPro (External, Reliable)

The most flexible approach is to expose an HTTP endpoint in your Heroku app and let an external cron-as-a-service call it on schedule. CronJobPro handles the scheduling, monitoring, and alerting while your app just responds to HTTP requests.

Step 1: Create a Secured Endpoint

// Express.js example
const express = require('express');
const app = express();

// Middleware to verify cron secret
function verifyCronSecret(req, res, next) {
  const secret = req.headers['x-cron-secret'];
  if (secret !== process.env.CRON_SECRET) {
    return res.status(401).json({ error: 'Unauthorized' });
  }
  next();
}

app.post('/api/cron/cleanup', verifyCronSecret, async (req, res) => {
  try {
    const deleted = await cleanupExpiredSessions();
    res.json({ success: true, deleted });
  } catch (err) {
    res.status(500).json({ error: err.message });
  }
});

app.post('/api/cron/daily-report', verifyCronSecret, async (req, res) => {
  try {
    await generateDailyReport();
    res.json({ success: true });
  } catch (err) {
    res.status(500).json({ error: err.message });
  }
});

Step 2: Configure CronJobPro

In the CronJobPro dashboard, create a monitor for each endpoint:

• •URL: https://your-app.herokuapp.com/api/cron/cleanup
• •Method: POST
• •Header: X-Cron-Secret: your-secret-value
• •Schedule: 0 * * * * (every hour)
• •Timezone: Your preferred timezone

CronJobPro calls the endpoint on schedule and tracks every execution. If the endpoint returns a non-2xx status code or does not respond within the timeout, you get an alert via email, Slack, or webhook.

Comparison Table

For non-critical tasks where missing an occasional execution is acceptable, Heroku Scheduler works. For everything else, use Cron To Go if you want to stay within the Heroku ecosystem, or CronJobPro if you want monitoring and alerting with the flexibility to work across any platform.

Frequently Asked Questions