About
Why DevToolbox exists: a fast, private, no-nonsense collection of developer tools that run entirely in your browser.
What this is
DevToolbox is a set of small, focused utilities for developers, sysadmins, technical writers, and anyone who regularly wrangles structured text. It covers format conversion between JSON, YAML, TOML, XML, CSV and Markdown; text and code helpers such as diffing, case conversion, slug generation and word counting; encoders and generators for Base64, URL escaping, hashes, UUIDs, QR codes and passwords; timestamp and timezone tools; and base conversion between binary, octal, decimal and hexadecimal. Each tool does one narrow job and does it immediately, with no sign-up wall and no multi-step wizard in the way.
Why everything runs in your browser
Every tool on this site is implemented in plain JavaScript that executes on your own machine, using standard web platform APIs: Web Crypto for hashing, Intl.DateTimeFormat for timezone math, DOMParser for XML, and TextEncoder for byte-level work. There is no backend server, no database, and no user account. The practical consequences matter more than the architecture: the text you paste never travels across the network, so you can safely format a config file or hash a token from a private repository; pages respond instantly because there is no round trip; and the site keeps working even when your connection drops.
Who maintains it
DevToolbox is built and maintained by an independent developer who spent too many years bouncing between tool sites that were slow, cluttered with interstitials, or quietly uploading pasted input to a server for processing. This site is the deliberate opposite: one stylesheet, no framework, no tracking beyond basic aggregate analytics, and no upload path for your data. Corrections and tool requests are read personally — see the contact page.
The standards behind the tools
The tools rest on public, stable specifications rather than on anyone's proprietary behaviour: RFC 3339 and ISO 8601 for timestamps, the IANA timezone database surfaced through Intl, RFC 4648 for Base64 and Base32 alphabets, RFC 4122 for UUID version 4, WCAG 2.1 relative-luminance maths for contrast ratios, POSIX and Quartz conventions for cron expressions, and the YAML 1.2 and TOML 1.0 specifications for those formats. These specifications change rarely, if ever. That is a deliberate selection criterion: it means the output you get today will still be correct next year without the site needing constant revision.
What this site is not
DevToolbox is not a security product, a compliance tool, or a substitute for professional review. Hash and password helpers are convenience utilities for development work, not a key-management system. Converters aim for faithful structural translation, but exotic edge cases in any format can behave differently across parser implementations. Always review output before it reaches production.