I built 12 free, no-upload browser tools — here's how (and why)

Every few weeks I'd hit the same wall while shipping my own apps: I need to compress an image under a size limit, make a Wi-Fi QR code, resize an icon to an exact pixel size, or generate a privacy policy for a Play Store listing. I'd Google it, land on some tool, and... upload my file to a stranger's server, dodge an ad, or make an account — for a job the browser can already do locally.

So I built my own set instead, with one rule: everything runs client-side. Nothing is uploaded.

It's now 12 free tools at nasrtech.dev/tools. Here's the how and the why.

The core idea: the browser is enough

Most of these tasks don't need a backend at all. Modern browser APIs do the heavy lifting:

• Images (resize, compress, convert PNG/JPG/WebP) → the <canvas> API + canvas.toBlob(). The file is read with FileReader, drawn to a canvas, re-encoded at the quality/size you pick, and handed back as a download. It never touches a network.
• Passwords → the Web Crypto API (crypto.getRandomValues) for cryptographically secure randomness, instead of Math.random().
• QR codes, sitemaps, privacy policies, meta tags, color/case/word tools → plain string and DOM work. No server, no database.

The whole thing is vanilla JS and static HTML/CSS. No framework, no build step for most pages, no analytics-on-your-files. That's not a purity flex — it's the feature. When the processing is local, "is my data safe?" stops being a trust question and becomes a fact of how the tool is built.

What's in the set

• Image Compressor — shrink JPG/PNG/WebP, often by 70–90%, you choose the quality.
• Resize Image — by pixels, %, or presets (YouTube thumb, app icon, IG, OG image).
• Image Format Converter — PNG/JPG/WebP, in batches.
• QR Code Generator — links, Wi-Fi, WhatsApp, text, vCard — with colors and a logo.
• Sitemap Generator — XML + HTML + robots.txt from a URL list.
• Privacy Policy Generator — Android/iOS/website, only the clauses you need.
• Meta Tag Generator — title, description, Open Graph, Twitter Card, live preview.
• Password Generator — strong random or memorable passphrases.
• Color Converter — HEX/RGB/HSL/HSV/CMYK/OKLCH, with a picker.
• Word Counter, Case Converter, and in-browser PDF tools (images→PDF, merge, split).

A few honest gotchas

• Big images can briefly freeze the tab while the canvas encodes — I moved the compressor's heavy work into a Web Worker so the UI stays responsive.
• WebP/AVIF encoding support varies by browser; I feature-detect and fall back.
• No-upload ≠ magic — for OCR/scanning on a phone you still want a real app, so that part lives in a separate Android app, not the web tools.

Why I'm sharing it

I'm not trying to out-feature TinyPNG or Canva. The pitch is narrower and, I think, honest: small, single-purpose tools that don't ask you to upload, sign up, or pay. If that's useful to you, it's all free here → nasrtech.dev/tools.

What's the one tiny tool you keep re-googling and re-uploading files to? I'm taking requests for the next batch. 👇