Run unsafe user generated JavaScript in the browser

In plain words

This tool allows developers to safely execute user-generated JavaScript code in the browser by running it in a web worker on a separate domain, isolating it from the main site. It's designed for developers building platforms that need to support user-created plugins or extensions. The solution includes a sandbox security model and an interactive demo where users can write and test code directly in the browser.

written from the facts on this page · September 2026

From the sources

A secure sandbox for you to run end user JavaScript safely away from your own application. The following is a demo of using WorkerBox to create a plugin architecture for a web UI. There are messages on the right, and an action bar that you can add commands to. It will be impossible for you to effect the DOM of this page, without using the deliberately exposed methods on the scope. For this demo, you can't edit the scope, as it's hard coded into the demo app. You can edit the code below and see the results on the right. Running How does it work? An iframe is inserted into the page from a completely separate domain. The iframe then creates a web worker, and handles posting messages between…from workerbox.net

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