The latest articles on DEV Community by TAPAS MAHATA (@tapas_mahata). https://dev.to/tapas_mahata 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%2F4112912%2Ff3f0ba91-c362-4fe4-8f29-fc460616229d.jpg https://dev.to/tapas_mahata en TAPAS MAHATA Sun, 06 Sep 2026 23:59:34 +0000 https://dev.to/tapas_mahata/i-built-93-free-browser-based-tools-for-developers-no-signup-no-upload-54g7 https://dev.to/tapas_mahata/i-built-93-free-browser-based-tools-for-developers-no-signup-no-upload-54g7 <h1> I Built 93+ Free Browser-Based Tools for Developers — No Signup, No Upload </h1> <p>I'm a teacher and self-taught web developer from India. Over the past few months, I built <strong><a href="https://tsmtools.in" rel="noopener noreferrer">TSM Tools</a></strong> — a completely free, browser-based toolkit with 93+ tools for developers, SEO professionals, and students.</p> <p>No backend. No database. No signup. Everything runs 100% in your browser — your files and data never leave your device.</p> <p>Here's what I built and why.</p> <h2> 🤔 Why I Built This </h2> <p>I was tired of switching between 10 different websites just to:</p> <ul> <li>Format a JSON response</li> <li>Check keyword density of a blog post</li> <li>Generate a QR code</li> <li>Calculate an EMI</li> <li>Decode a JWT token</li> </ul> <p>Most of these tools either require signup, show aggressive ads, or upload your files to their server. I wanted something <strong>fast, private, and free</strong> — so I built it myself.</p> <h2> 🛠 What's Inside </h2> <h3> Developer Tools (24 tools) </h3> <ul> <li> <strong>JSON Formatter &amp; Validator</strong> — beautify or minify JSON instantly</li> <li> <strong>JS / CSS / HTML Formatter</strong> — format messy code in one click</li> <li> <strong>JS / CSS Minifier</strong> — reduce file size for production</li> <li> <strong>JWT Decoder</strong> — inspect tokens without any library</li> <li> <strong>.htaccess Generator</strong> — build Apache redirect rules visually</li> <li> <strong>Cron Expression Builder</strong> — create cron schedules with plain-English preview</li> <li> <strong>Base Converter</strong> — Binary ↔ Decimal ↔ Hex ↔ Octal</li> <li> <strong>SQL Formatter</strong> — format raw SQL queries</li> <li> <strong>Regex Tester</strong> — test regular expressions with live matches</li> <li>And more...</li> </ul> <h3> 🔄 Converters (26 tools) </h3> <ul> <li> <strong>Excel Viewer</strong> — open .xlsx, .xls, .ods with multi-sheet support</li> <li> <strong>Excel → JSON / CSV / HTML</strong> — export spreadsheet data instantly</li> <li> <strong>CSV → Excel / JSON → Excel</strong> — download as .xlsx in one click</li> <li> <strong>JSON ↔ CSV ↔ XML</strong> — convert data formats instantly</li> <li> <strong>Image Compressor</strong> — reduce file size with quality slider</li> <li> <strong>Image Resizer</strong> — custom dimensions with aspect ratio lock</li> <li> <strong>Format Converter</strong> — PNG ↔ JPEG ↔ WebP</li> <li> <strong>PDF to HTML</strong> — each page rendered as image, exact visual copy</li> <li> <strong>Word to HTML</strong> — convert .docx to HTML markup</li> <li> <strong>Markdown ↔ HTML</strong> — live preview conversion</li> <li> <strong>Text ↔ Binary / Hex / Morse Code</strong> — encode and decode instantly</li> </ul> <h3> ⚡ Utilities (21 tools) </h3> <ul> <li> <strong>EMI Calculator</strong> — home, car, personal loans with tenure quick-select</li> <li> <strong>BMI Calculator</strong> — metric and imperial with health range</li> <li> <strong>Age Calculator</strong> — exact age with next birthday countdown</li> <li> <strong>QR Code Generator</strong> — URL, text, contact info</li> <li> <strong>Invoice Generator</strong> — create and print professional invoices</li> <li> <strong>Unit Converter</strong> — length, weight, temperature, speed, area, data</li> <li> <strong>Password Generator</strong> — with strength indicator</li> <li> <strong>IP Address Lookup</strong> — detect your current IP instantly</li> <li> <strong>Color Picker</strong> — HEX, RGB, HSL values</li> <li> <strong>Word Counter</strong> — characters, sentences, reading time</li> </ul> <h3> 📈 SEO Tools (21 tools) </h3> <ul> <li> <strong>SERP Preview</strong> — see how your page looks in Google search</li> <li> <strong>Keyword Density Checker</strong> — analyze keyword usage</li> <li> <strong>Meta Tag Generator</strong> — create optimized title and description</li> <li> <strong>Sitemap Generator</strong> — create XML sitemaps for Google Search Console</li> <li> <strong>Schema Markup Generator</strong> — JSON-LD structured data</li> <li> <strong>Twitter Card Preview</strong> — see how links look when shared</li> <li> <strong>HTTP Header Checker</strong> — inspect response headers</li> <li> <strong>Core Web Vitals Guide</strong> — LCP, FID, CLS explained</li> </ul> <h3> 🔬 PHP/JS/HTML Health Checker </h3> <p>This is the tool I'm most proud of. Upload a ZIP file of your PHP, JavaScript, or HTML project and get:</p> <ul> <li>SQL injection vulnerability detection</li> <li>XSS vulnerability scanning</li> <li>JavaScript syntax checking</li> <li>Security best practice analysis</li> <li>Auto-fix suggestions</li> </ul> <p>All scanning happens in your browser using JavaScript — your code is never uploaded to any server.</p> <h2> 🏗 How I Built It </h2> <p>Everything is vanilla HTML, CSS, and JavaScript — no frameworks, no build tools.</p> <p><strong>Key libraries used:</strong></p> <ul> <li> <a href="https://sheetjs.com/" rel="noopener noreferrer">SheetJS (xlsx)</a> — Excel file reading and writing</li> <li> <a href="https://github.com/mwilliamson/mammoth.js" rel="noopener noreferrer">Mammoth.js</a> — Word to HTML conversion</li> <li> <a href="https://mozilla.github.io/pdf.js/" rel="noopener noreferrer">PDF.js</a> — PDF rendering on canvas</li> <li> <a href="https://davidshimjs.github.io/qrcodejs/" rel="noopener noreferrer">QRCode.js</a> — QR code generation</li> </ul> <p><strong>What I learned:</strong></p> <ul> <li>Browser APIs are incredibly powerful — File API, Canvas API, Blob API, URL.createObjectURL()</li> <li>You can do a lot without a backend if you design around client-side processing</li> <li>Keeping everything in one HTML file per page makes deployment trivially simple</li> </ul> <h2> 📊 The Numbers </h2> <div class="table-wrapper-paragraph"><table> <thead> <tr> <th>Category</th> <th>Tools</th> </tr> </thead> <tbody> <tr> <td>Dev Tools</td> <td>24</td> </tr> <tr> <td>Converters</td> <td>26</td> </tr> <tr> <td>Utils</td> <td>21</td> </tr> <tr> <td>SEO Tools</td> <td>21</td> </tr> <tr> <td>Health Checker</td> <td>1</td> </tr> <tr> <td><strong>Total</strong></td> <td><strong>93+</strong></td> </tr> <tr> <td>Blog Articles</td> <td>24</td> </tr> </tbody> </table></div> <h2> 🚀 What's Next </h2> <ul> <li>More Excel tools (pivot table viewer, formula helper)</li> <li>More SEO tools (backlink checker, page speed analyzer)</li> <li>Dark mode</li> <li>Mobile app (PWA)</li> </ul> <h2> 🔗 Try It </h2> <p>👉 <strong><a href="https://tsmtools.in" rel="noopener noreferrer">https://tsmtools.in</a></strong></p> <p>All tools are free, forever. No signup. No upload. No tracking beyond basic analytics.</p> <p>I'd love to hear your feedback — what tools do you use most? What's missing? Drop a comment below! 👇</p> <p><em>Built with ❤️ by a teacher who codes.</em></p> webdev javascript php tools