CodingInterview
AlgoExpert.io
Interview Cake
interviewing.io
Daily Coding Problem
Codechef
CodeForces
LogicMojo
CodeUtil.dev
CodifyFormatter.org
DevToys
DuskTools.app
Text-Utils JSON Formatter
CyberChef
150+ Developer Tools
CodersTool
CodeUtil.dev is a collection of 20+ browser-based developer tools. JSON formatter & validator, regex tester, cron expression generator, Base64 encoder/decoder, JWT debugger, URL parser, hash generator, and more. Everything runs client-side โ no data leaves your browser. No sign-up needed, just open and use.
CodingInterview
CodeUtil.devCodeUtil.dev's answer:
CodeUtil.dev runs entirely in the browser โ all processing happens on your device, so your data never touches a server. It bundles 20+ tools (JSON, regex, Base64, JWT, cron, hashing, and more) under one roof with zero sign-up. Just open the page and start working.
AlgoExpert.io - A better way to prep for tech interviews
CodifyFormatter.org - Free Online Tools like Beautify Code, Minifiy Code, Code Converter, Code Formatter, Viewer, Editor for Developer: JSON, XML, HTML, CSS, JavaScript, Java, SQL, CSV and Excel and String Tools
Interview Cake - Free practice programming interview questions. Interview Cake helps you prep for interviews to land offers at companies like Google and Facebook.
DevToys - A collection of converters, formaters, encoders, generators and other tools for your Windows desktop.
interviewing.io - Free, anonymous technical interview practice
DuskTools.app - 150+ free browser-based developer tools - no sign-up, no tracking, no backend. JSON formatter, Base64 encoder, regex tester, JWT decoder, UUID generator, HTTP status lookup, MIME types, port reference, cron builder & more. Everything runs locally in