The latest articles on DEV Community by dinhvancntt (@dinhvancntt). https://dev.to/dinhvancntt 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%2F982901%2F85e2a02a-5ba6-4eb5-bad6-cddc0c3dbce9.jpeg https://dev.to/dinhvancntt en dinhvancntt Sat, 03 Oct 2026 08:11:08 +0000 https://dev.to/dinhvancntt/-1n65 https://dev.to/dinhvancntt/-1n65 <div class="ltag__link--embedded"> <div class="crayons-story "> <a href="https://dev.to/dinhvancntt/i-built-79-free-developer-tools-with-astro-no-sign-up-mostly-client-side-3805" class="crayons-story__hidden-navigation-link">I built 79 free developer tools with Astro – no sign-up, mostly client-side</a> <div class="crayons-story__body crayons-story__body-full_post"> <div class="crayons-story__top"> <div class="crayons-story__meta"> <div class="crayons-story__author-pic"> <a href="/dinhvancntt" class="crayons-avatar crayons-avatar--l "> <img src="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F982901%2F85e2a02a-5ba6-4eb5-bad6-cddc0c3dbce9.jpeg" alt="dinhvancntt profile" class="crayons-avatar__image"> </a> </div> <div> <div> <a href="/dinhvancntt" class="crayons-story__secondary fw-medium m:hidden"> dinhvancntt </a> <div class="profile-preview-card relative mb-4 s:mb-0 fw-medium hidden m:inline-block"> dinhvancntt <div id="story-author-preview-content-4791026" class="profile-preview-card__content crayons-dropdown branded-7 p-4 pt-0"> <div class="gap-4 grid"> <div class="-mt-4"> <a href="/dinhvancntt" class="flex"> <span class="crayons-avatar crayons-avatar--xl mr-2 shrink-0"> <img src="https://media2.dev.to/dynamic/image/width=800%2Cheight=%2Cfit=scale-down%2Cgravity=auto%2Cformat=auto/https%3A%2F%2Fdev-to-uploads.s3.us-east-2.amazonaws.com%2Fuploads%2Fuser%2Fprofile_image%2F982901%2F85e2a02a-5ba6-4eb5-bad6-cddc0c3dbce9.jpeg" class="crayons-avatar__image" alt=""> </span> <span class="crayons-link crayons-subtitle-2 mt-5">dinhvancntt</span> </a> </div> <div class="print-hidden"> Follow </div> <div class="author-preview-metadata-container"></div> </div> </div> </div> </div> <a href="https://dev.to/dinhvancntt/i-built-79-free-developer-tools-with-astro-no-sign-up-mostly-client-side-3805" class="crayons-story__tertiary fs-xs"><time>Oct 3</time><span class="time-ago-indicator-initial-placeholder"></span></a> </div> </div> </div> <div class="crayons-story__indention"> <h2 class="crayons-story__title crayons-story__title-full_post"> <a href="https://dev.to/dinhvancntt/i-built-79-free-developer-tools-with-astro-no-sign-up-mostly-client-side-3805" id="article-link-4791026"> I built 79 free developer tools with Astro – no sign-up, mostly client-side </a> </h2> <div class="crayons-story__tags"> <a class="crayons-tag crayons-tag--filled " href="/t/showdev"><span class="crayons-tag__prefix">#</span>showdev</a> <a class="crayons-tag crayons-tag--monochrome " href="/t/webdev"><span class="crayons-tag__prefix">#</span>webdev</a> <a class="crayons-tag crayons-tag--monochrome " href="/t/javascript"><span class="crayons-tag__prefix">#</span>javascript</a> <a class="crayons-tag crayons-tag--monochrome " href="/t/astro"><span class="crayons-tag__prefix">#</span>astro</a> </div> <div class="crayons-story__bottom"> <div class="crayons-story__details"> <a href="https://dev.to/dinhvancntt/i-built-79-free-developer-tools-with-astro-no-sign-up-mostly-client-side-3805" class="crayons-btn crayons-btn--s crayons-btn--ghost crayons-btn--icon-left"> <div class="multiple_reactions_aggregate"> <span class="multiple_reactions_icons_container"> <span class="crayons_icon_container"> <img src="https://assets.dev.to/assets/sparkle-heart-5f9bee3767e18deb1bb725290cb151c25234768a0e9a2bd39370c382d02920cf.svg" width="18" height="18"> </span> </span> <span class="aggregate_reactions_counter">2<span class="hidden s:inline">&nbsp;reactions</span></span> </div> </a> <a href="https://dev.to/dinhvancntt/i-built-79-free-developer-tools-with-astro-no-sign-up-mostly-client-side-3805#comments" class="crayons-btn crayons-btn--s crayons-btn--ghost crayons-btn--icon-left flex items-center"> <span class="hidden s:inline">Add&nbsp;Comment</span> </a> </div> <div class="crayons-story__save"> <small class="crayons-story__tertiary fs-xs mr-2"> 2 min read </small> </div> </div> </div> </div> </div> </div> productivity showdev tools webdev dinhvancntt Sat, 03 Oct 2026 08:07:46 +0000 https://dev.to/dinhvancntt/i-built-79-free-developer-tools-with-astro-no-sign-up-mostly-client-side-3805 https://dev.to/dinhvancntt/i-built-79-free-developer-tools-with-astro-no-sign-up-mostly-client-side-3805 <p>I got tired of ad-covered, sign-up-walled utility sites, so I spent the last few weeks building my own toolbox: <strong>79 free developer tools</strong> at <a href="https://devtoolbelt-tools.vercel.app/" rel="noopener noreferrer">https://devtoolbelt-tools.vercel.app/</a></p> <p>A few I actually use myself:</p> <ul> <li> <strong>UULE Generator</strong> (<a href="https://devtoolbelt-tools.vercel.app/tools/uule-generator" rel="noopener noreferrer">https://devtoolbelt-tools.vercel.app/tools/uule-generator</a>) — generate Google's location parameter to simulate local search from any city. I verified the protobuf encoding byte-for-byte against published test vectors.</li> <li> <strong>UUID v4 + v7</strong> (<a href="https://devtoolbelt-tools.vercel.app/tools/uuid-generator" rel="noopener noreferrer">https://devtoolbelt-tools.vercel.app/tools/uuid-generator</a>) — bulk generation, time-ordered v7 per RFC 9562.</li> <li> <strong>JSON to CSV</strong> (<a href="https://devtoolbelt-tools.vercel.app/tools/json-to-csv" rel="noopener noreferrer">https://devtoolbelt-tools.vercel.app/tools/json-to-csv</a>) — nested objects flattened, RFC 4180 quoting.</li> <li> <strong>Extract Regex Matches</strong> (<a href="https://devtoolbelt-tools.vercel.app/tools/extract-regex-matches-from-text" rel="noopener noreferrer">https://devtoolbelt-tools.vercel.app/tools/extract-regex-matches-from-text</a>) — with capture groups, presets for emails/URLs/numbers.</li> <li> <strong>Google SERP Preview</strong> (<a href="https://devtoolbelt-tools.vercel.app/tools/serp-preview" rel="noopener noreferrer">https://devtoolbelt-tools.vercel.app/tools/serp-preview</a>) — pixel-width meter (600px title), desktop/mobile views.</li> </ul> <p>Plus the usual suspects: Base64/URL/HTML/hex/binary encoders, Morse code, ROT13/47, case converters, word counters, password generator, test credit card numbers (Luhn-valid, test-only), and more.</p> <p><strong>How it's built:</strong></p> <ul> <li>Astro, fully static. Every tool is the same 6-file pattern: pure <code>logic.ts</code> + <code>logic.test.ts</code> + UI.</li> <li>~2,300 Vitest tests. Logic never touches the DOM, so everything is unit-tested.</li> <li>Anything that can run client-side does — most tools never send your input to a server. Nothing is stored.</li> <li>Each page ships SEO meta + FAQ schema.</li> </ul> <p><strong>What I'm figuring out now:</strong> which tools deserve to exist. Search Console says my Google Search URL generator and 2FA tool get the most impressions, so I'm doubling down on the search/dev cluster next.</p> <p>What small utility do you wish existed? Genuinely taking requests — if it's a pure function, I can usually ship it the same day.</p> showdev webdev javascript astro