Dev Tools

Regex Matches Nothing / Greedy .* Swallows Results — How to Fix

Online regex test matches nothing, or greedy .* eats too much, or groups capture nothing? Explains greedy vs lazy, escaping special chars, and anchors — with a step-by-step debug using our regex tester.

API Testing: How to Send a Token and Fix CORS Errors

How to add an Authorization token when testing APIs online, and what to do about CORS / 405 / timeout errors? A step-by-step troubleshooting guide with our API tester.

Mock Data Generator Complete Guide: Generate Test Data Fast

Generate reproducible test rows with field types, locale samples, and seeds. Export JSON, CSV, TSV, YAML, or SQL for frontend mocks and local DB seeding.

JSON to TypeScript: Complete Guide to Auto-Generating Type Definitions

Step-by-step tutorial on how to quickly convert JSON data to TypeScript interfaces and type definitions, boosting development efficiency and code quality

.gitignore Generator Guide: Stack Combos, Deduping, and Custom Rules

Learn .gitignore syntax, already-tracked file pitfalls, and how to combine language, framework, IDE, tool, and OS templates—with automatic dedupe and custom lines—in the online generator.