The latest articles on DEV Community by Zhang Enquan (@devenquan). https://dev.to/devenquan 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%2F4106337%2F104d7bf2-22ff-405e-a91b-9f2cec4a68df.jpeg https://dev.to/devenquan en Zhang Enquan Wed, 02 Sep 2026 14:50:11 +0000 https://dev.to/devenquan/i-built-35-browser-side-tools-because-i-was-tired-of-uploading-my-data-to-random-servers-4h9n https://dev.to/devenquan/i-built-35-browser-side-tools-because-i-was-tired-of-uploading-my-data-to-random-servers-4h9n <p>Every time I needed to format a JSON payload or compress an image, I found myself on some random tool site with three problems:</p> <ol> <li> <strong>My data went to their server.</strong> Paste a password or an API token into a "hash generator" and you're just trusting that site not to log it.</li> <li> <strong>Ads everywhere.</strong> The tool was buried under banners, and half the buttons were ad-click traps.</li> <li> <strong>Sign-up walls.</strong> Want to download your converted file? Create an account first.</li> </ol> <p>So I built <a href="https://aisubtools.xyz" rel="noopener noreferrer">AI SubTools</a> — a collection of 35+ free tools where <strong>everything runs client-side in JavaScript</strong>. No uploads. No accounts. No ads.</p> <h2> Why client-side matters </h2> <p>It's not just a privacy stance. When the tool runs in your browser:</p> <ul> <li> <strong>It's instant.</strong> No round-trip to a server, no queue. Image compression happens as fast as your CPU allows.</li> <li> <strong>It works offline</strong> once the page is loaded.</li> <li> <strong>Your data never leaves your device.</strong> For tools that touch passwords, tokens, or checksums, this should be the default, not a feature.</li> </ul> <h2> Some of the more interesting tools </h2> <ul> <li> <strong>Cron expression generator &amp; tester</strong> — with plain-English explanations of what your expression actually does</li> <li> <strong>PNG background remover</strong> — runs entirely in-browser, no upload</li> <li> <strong>Robots.txt + XML sitemap generator</strong> — for the SEO-minded</li> <li> <strong>EAN/UPC barcode creator</strong> — for e-commerce sellers</li> <li> <strong>JSON formatter &amp; validator, Base64 encoder/decoder, MD5/SHA-256 generators</strong> — the daily-driver classics</li> </ul> <h2> The technical trade-offs </h2> <p>The hardest parts were making <strong>image compression</strong> and <strong>background removal</strong> perform well without WASM. Canvas-based processing is fast enough for most images, but there's a real art to avoiding UI freezes on large files — chunked processing and careful memory management matter more than raw algorithm speed.</p> <h2> What's next </h2> <p>The site is a side project that grew out of my own daily frustration. New tools are added regularly, and I'm currently prioritizing:</p> <ul> <li>More file-format converters</li> <li>Better mobile experience for the image tools</li> </ul> <p><strong>What tools would you want added?</strong> I'd genuinely love to hear what's missing from your daily workflow — the best suggestions will get built.</p> <p><em>P.S. Everything is free, forever. No premium tier hiding the useful stuff.</em></p> webdev showdev productivity opensource