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DevTools.best - Most frequent used dev tools

Repl.it - The collaborative browser based IDE

CODELF - search for variable name

Semver checker

BundlePhobia ❘ cost of adding a npm package

Regex101

JSON Editor Online

CodePen

CodeSandbox

Learn X in Y Minutes

Devhints — TL;DR for developer documentation

DevDocs

Refactoring Guru

Crontab.guru - The cron schedule expression editor

explainshell.com - Explain a shell command

.htaccess tester

Transfonter - @font-face generator

Google Fonts

Flaticon

Font Awesome Icons

The stocks

Photopea | Online Photo Editor

Google, but for colors

Coolors - color palettes