Code Testing — 8 Free Online Tools
8 free online code testing. No signup required.
Test and validate code: regex patterns, JWT tokens, grammar, text diffs, math problems, and typing. Free developer tools for everyday coding tasks.
Code Minifier & Beautifier - JS, CSS, HTML
Free online code minifier and beautifier. Minify JS, CSS, HTML for production or beautify for debugging. Size stats, copy, all in browser. No signup.
Free Grammar Checker - AI Error Explanation
Free AI grammar checker that not only corrects your English but explains why it's wrong. Perfect for learning proper grammar rules.
Free Online Math Solver - Step-by-Step Solutions
Free online math solver with step-by-step solutions. Solve algebra, equations, fractions, and more. No signup required, instant results.
Free Text Diff Checker - Compare Text & Code Online
Free online text diff checker to compare text and code. Side-by-side view with syntax highlighting. Compare JSON, XML, code files and find differences.
Free Typing Test - WPM, Accuracy & Code Mode
Free online typing test with WPM, accuracy, and code snippet modes (JavaScript, Python, SQL, HTML). No signup. Practice common words, quotes, numbers, and programming syntax. Privacy-first.
HTML Playground - Live HTML CSS JS Code Editor with Preview
Free online HTML playground with live preview. Write and test HTML, CSS, and JavaScript instantly. No signup, 100% private browser processing. AI cannot run your code - we do.
JWT Decoder - Decode & Verify Tokens
Free JWT decoder. Decode tokens, inspect claims, verify signatures in your browser.
Regex Tester - Test Regular Expressions
Test regular expressions with real-time matching. Supports g, i, m, s flags. See match count and captured groups.