// free developer tools · browser-based · no signup · no data collection
ByteUtilities is a free collection of online developer tools that run entirely in your browser. Whether you need to format a JSON response, decode a JWT token, test a regular expression, generate a secure password, or convert between color formats — ByteUtilities has a dedicated tool for it, available instantly without creating an account.
The site was built out of frustration with existing online tools that require signups, show intrusive ads, impose rate limits, or — most concerning — process your sensitive data on their servers. A tool that asks you to paste your JWT token or API keys into a form and submit it to a server is a security risk. Every ByteUtilities tool that works on data you provide — formatting, decoding, hashing, generating — processes it locally using your browser's own JavaScript engine. A handful of newer tools look up genuinely public information (a domain's DNS records, an npm package's registry entry, a currency exchange rate) and, for those, your query goes directly from your browser to that public data source — never through a ByteUtilities server. See "How the tools work" below for exactly which tools do which.
We currently offer 18 free developer utilities, with more in active development:
Every tool on ByteUtilities is built with plain HTML, CSS, and JavaScript, and there is no ByteUtilities backend server processing your data — we don't operate one. Most tools (JSON Formatter, Base64, URL Encoder, Regex Tester, JWT Decoder, UUID Generator, Password Generator, Hash Generator, Timestamp Converter, Color Converter, Diff Checker, Word Counter, User-Agent Parser) do all their work inside your browser tab using JavaScript APIs like JSON.parse() and the Web Crypto API — nothing you type into these ever leaves your device.
Six tools look up or generate data via a third-party API, called directly from your browser (not relayed through any ByteUtilities server):
registry.npmjs.org)dns.google)None of these six send anything to ByteUtilities itself — we don't run the servers behind any of them and have no visibility into what you look up or generate. For everything else, this architecture means:
ByteUtilities displays Google AdSense advertisements to cover hosting and domain costs. These ads may use cookies to show relevant content based on your browsing history. You can opt out of personalised advertising at Google Ads Settings.
We use Google Analytics to understand anonymous aggregate traffic patterns — which tools are most used, which pages people visit, and where traffic comes from. No personally identifiable information is collected through analytics. Your tool inputs are never logged or transmitted by ByteUtilities — see "How the tools work" above for the handful of tools that query a public third-party API directly.
For full details, see our Privacy Policy.
All tools are built to follow their respective specifications: JSON tools follow RFC 8259, URL encoding follows RFC 3986, hash functions follow NIST standards, and UUID generation follows RFC 4122. The regex tester uses JavaScript's native RegExp engine — results may differ slightly from Python's re module or other regex flavours.
While we test all tools carefully, ByteUtilities is provided as-is without warranty. For production-critical operations, always verify results independently.
Found a bug? Have a tool request? We'd genuinely like to hear from you.