crontab is described as 'CRONTAB EDITING MADE SIMPLE'. There are nine alternatives to crontab, not only websites but also apps for a variety of platforms, including Google Chrome, Looper, Webcron and Firefox. The best alternative is crontab guru, which is both free and Open Source. Other great sites and apps similar to crontab are EasyCron (Freemium), Cron As A Service (Paid), Looper (Paid) and YouXube - Repeat Youtube Videos (Free).
An easy to use editor for crontab schedules. Cron job failures can be disastrous! We created Cronitor because crontab itself can't alert you if your jobs fail or never start. With easy integration and instant alerts when things go wrong, Cronitor has you covered.
The Posthook API enables application developers to start scheduling tasks in minutes. Schedule one-off tasks for tomorrow or the first of next month by making a request to the API and setting up a webhook to process these tasks.
Cronicle is a multi-server task scheduler and runner, with a web based front-end UI. It handles both scheduled, repeating and on-demand jobs, targeting any number of slave servers, with real-time stats and live log viewer.