ShroomPen is a privacy-first browser writing assistant that lets you instantly reply, rewrite, fix grammar, or translate text across any website without sending sensitive data to the cloud. Designed to balance AI convenience with absolute data privacy, it keeps all your page, field, tab, and session context securely on your device, giving you complete control over your everyday web workflow.

Like many developers, I found myself constantly frustrated by the privacy trade-offs of modern AI writing tools. Every time I wanted a quick rewrite, grammar fix, or translation in the browser, I had to send sensitive webpage content, form data, and personal context to third-party cloud servers. I built ShroomPen to solve that exact problem: bringing the seamless convenience of an AI writing assistant directly to the browser while keeping 100% of the data local and private on the user's device. As I worked on the launch, my approach evolved from trying to build a heavy, feature-bloated extension to focusing tightly on a lightweight, context-aware utility. I realized that users don't want another complex app dashboard—they just want instant, secure help right inside the text fields they're already using, without ever having to worry about where their data is going.

Not having to leave the page is probably the part I’d appreciate most.

Translation built into the same little tool is a nice touch.

On device is a big plus.

Everyday use I could see myself reaching for this when I’ve written something that technically makes sense but sounds awkward. Being able to fix it right there without opening another tool feels genuinely convenient.

Not having to leave the page is probably the part I’d appreciate most.

Translation built into the same little tool is a nice touch.

On device is a big plus.

ShroomPen

Reply, rewrite, fix grammar, translate with single extension

Reply, rewrite, fix grammar, translate with single extension