The latest articles on DEV Community by PabloFede (@pablo_fede_20). https://dev.to/pablo_fede_20 https://media2.dev.to/dynamic/image/width=90,height=90,fit=cover,gravity=auto,format=auto/https:%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F4058532%2F685f7b13-aa57-47a9-bec9-a80acafe2758.png https://dev.to/pablo_fede_20 en PabloFede Sun, 02 Aug 2026 00:05:26 +0000 https://dev.to/pablo_fede_20/i-built-38-free-browser-only-tools-that-never-upload-your-files-1nhe https://dev.to/pablo_fede_20/i-built-38-free-browser-only-tools-that-never-upload-your-files-1nhe <p>Every time I needed to "compress an image online" or "merge a PDF", I ended up on some site that makes you upload your file to their server. For a random meme, fine. For a contract, an ID scan, or anything private? No thanks.</p> <p>So I built <a href="https://quickkit.space" rel="noopener noreferrer">QuickKit</a> — a growing kit of 38 free tools that run 100% in your browser. Your files and text never leave your device. No signup, no watermarks, no tracking of what you process.</p> <h2> How it works (the fun part) </h2> <p>The whole thing is a static site — no backend, no database, no server cost. Everything happens client-side with browser APIs:</p> <ul> <li> <strong>Image compressor / resizer</strong> → the Canvas API (<code>canvas.toBlob(type, quality)</code>)</li> <li> <strong>Image → PDF / Merge PDF</strong> → jsPDF and pdf-lib, entirely in-page</li> <li> <strong>Password / UUID generators</strong> → the Web Crypto API (<code>crypto.getRandomValues</code>) for real cryptographic randomness</li> <li> <strong>QR codes</strong> → generated locally, no redirect or tracking baked in</li> <li> <strong>Hash generator (SHA-256/1/512)</strong> → the SubtleCrypto API</li> <li> <strong>Countdown timer &amp; "days since" counters</strong> → shareable via the URL itself (state encoded in query params), so there's still no backend</li> </ul> <p>Because nothing is uploaded, the tools are faster and more private than upload-based services — and they even work offline once loaded (it's an installable PWA).</p> <h2> A few of the tools </h2> <p>Files &amp; docs: image compressor, image resizer, image→PDF, merge PDF.<br> Dev utilities: JSON formatter, Base64, hash generator, UUID, timestamp converter, case converter.<br> Everyday: QR generator, word counter, unit/percentage/age calculators, world clock, "your life in weeks".</p> <h2> The privacy architecture, in one line </h2> <blockquote> <p>If the browser can do it, there's no reason to send the user's data to a server.</p> </blockquote> <p>That principle killed all the usual costs (no servers, no storage, no compliance headaches) and made privacy the default instead of a feature.</p> <p>Would love feedback — especially on tools you wish existed. What "online X converter" do you use that you wish ran locally?</p> <p>👉 <a href="https://quickkit.space" rel="noopener noreferrer">quickkit.space</a></p> webdev javascript showdev privacy