Everything Developers Need
Free tools, editors, calculators, and interview guides — no login, no installs.
Featured Tools
The tools developers reach for every day.
Regex Tester
Write, test and debug regular expressions with live match highlighting.
JSON Formatter
Beautify, validate and minify JSON. Instantly spot syntax errors.
JWT Decoder
Decode and inspect JSON Web Token headers, payloads and signatures.
Timestamp Converter
Convert Unix timestamps to readable dates — and back — in any timezone.
Password Generator
Generate strong, customizable passwords. Everything stays in your browser.
SQL Formatter
Reformat and beautify SQL queries for readability and code review.
HTML Encoder & Decoder
Encode and decode HTML entities instantly in your browser.
Base64 Encoder
Encode and decode Base64
Developer Tools
Encode, decode, format and validate data — entirely in your browser.
JSON Formatter
Format, validate and minify JSON online for free.
JWT Decoder
Decode JWT tokens and inspect claims securely in your browser.
Base64 Encoder
Encode and decode Base64
UUID Generator
Generate UUID v4 identifiers instantly and securely in your browser.
URL Encoder & Decoder
Encode and decode URLs instantly using a free online URL encoder and decoder.
Password Generator
Generate strong and secure random passwords instantly in your browser.
Timestamp Converter
Convert Unix timestamps to human-readable dates and convert dates to Unix timestamps instantly.
Regex Tester
Test, validate and debug regular expressions online with real-time matching.
Online Editors
Code playgrounds with live compilation and instant previews.
JavaScript Playground
Write, run and debug JavaScript code directly in your browser.
Online Python Editor
Write, edit, copy and download Python code online.
Online Java Editor
Write, edit, copy and download Java code online.
Online Ruby Editor
Write, edit, copy and download Ruby code online.
Calculators
Smart calculators for programming, math, and productivity.
Percentage Calculator
Percentage Calculator online for free.
Age Calculator
Calculate your exact age in years, months and days.
EMI Calculator
Calculate monthly loan EMI, interest payable and total payment.
SIP Calculator
Calculate SIP returns, maturity amount and wealth creation instantly.
Interview Preparation
Study guides for Angular, React, JavaScript, and System Design.
JavaScript Interview Questions
Top JavaScript interview questions and answers for freshers and experienced developers.
Angular Interview Questions
Angular interview questions and answers with practical examples.
ReactJS Interview Questions
Top ReactJS interview questions and answers with practical examples for beginners and experienced developers.
NodeJS Interview Questions
Top NodeJS interview questions and answers for freshers, experienced developers and senior engineers. Includes Event Loop, Streams, Cluster, Worker Threads, Authentication, Security and System Design discussions.