I Built 20+ Privacy-First Browser Tools That Never Upload Your Data (All Single-File)

Every "free online tool" I tried had the same catch: your file gets uploaded to somebody's server before anything happens. CSV with customer emails? Uploaded. Invoice PDF? Uploaded. Password list? You'd have to be brave.

So I went the other direction. I've spent the past few months building a collection of single-file HTML tools — each one is literally one .html file. You open it in your browser and everything runs locally with JavaScript. Nothing ever leaves your machine. No accounts, no server, no tracking, no "free tier" limits.

All 30+ of them are collected here (free online versions, no signup): goodyuanbo.github.io

Here's what's in the toolbox, grouped by what people actually ask me for:

I Built 20+ Privacy-First Browser Tools That Never Upload Your Data (All Single-File)

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