Cron Lens Chrome extension
#project, #webdev, #extension
May 9th 2026

Cron Lens Chrome extension

Cron Lens is the second of my set of chrome extension developer tools. It is a chrome extension that allows you to quickly see a human readable format behind every cron expression on a web page.

The idea for this extension came because in my daily job I sometimes have to deal with cronjobs and scheduled tasks. And I never really bothered to learn how cron expressions work. Of course by working on this extension I now know exactly how cron expressions work. But the extension still has a purpose to me. Because just like reading time on a digital clock is usually a lot faster than reading time on an analogue clock. The same principal applies here. Because I can easily see exactly when a cron task is scheduled to run it saves me time translating the expression in my mind.

If you want you can test this extension after downloading on this page, I added a cron expression at the bottom of this page. After installing the extension it is set to active mode by default and should already translate any cron expressions. You can also switch to passive mode and use the button in the popup to add context to all cron expression on a page.

The project is currently in a early stage but I'm planning on continuing developement on this extension and hopefully release it to the Chrome store in the future. But for now if you want to try out the project you can find the repository here including a startup guide to compile the code for yourself.

Try it out for yourself! * * * * *

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