ExtendsClass
Free Online Toolbox for developers
ExtendsClass is a free online toolbox for developers, web designers, and webmasters that provides a wide range of browser-based utilities. It solves the problem of needing to install separate software or browser extensions for common development tasks, as all tools run directly in the browser without any installation required.
The collection includes syntax validators, code formatters, and testers for languages such as PHP, Python, Ruby, JavaScript, Go, Java, and Lua. It also features HTTP API tools like a REST client, SOAP client, and a mock REST API server, along with database tools including an SQLite browser and online compilers for MySQL, PostgreSQL, SQL Server, Oracle, and MongoDB. Additional capabilities cover encoders and decoders, converters for formats like JSON, CSV, XML, and YAML, formatters, compare tools, and webmaster utilities such as sitemap and robots.txt generators, minifiers, and file compression tools.
The tools are aimed at developers, web designers, and webmasters who need quick, lightweight utilities without the overhead of local software. ExtendsClass is free to use, supported by advertising, and some tools are available as open source on GitHub. There is no mention of a paid plan, trial, or seat-based pricing.
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