⚙️Developer Tools
Online developer tools: format, test and convert JSON, RegEx, CSS, encodings and more – free in your browser, no sign-up.
43 free tools – right in your browser, no sign-up.
JSON Formatter & Validator
Format, validate and minify JSON – runs in the browser
JSON Diff
Compare two JSON structures – highlight differences with color
Diff Checker
Compare two texts line by line – runs in the browser
JWT Decoder
Decode and validate JSON Web Tokens
Base64 & URL Encoder
Encode/decode Base64 and URL parameters – runs in the browser
YAML ↔ JSON Converter
Convert between YAML and JSON – in the browser
XML → JSON
Convert XML to JSON – DOMParser in the browser, no upload
IEEE-754 Float Visualizer
Interactively analyze Float32/Float64 bits, sign, exponent and mantissa
HTML/CSS/JS Minifier & Beautifier
Minify or format HTML, CSS, JS and JSON – runs in the browser
Regex Tester
Interactively test and debug regular expressions
Docker Compose Generator
Generate docker-compose.yml for common services
Timestamp Converter
Convert Unix timestamps to date/time and vice versa
UUID Generator
Generate UUID v1, v4, v5 and ULID – directly in the browser
JSON to TypeScript
Convert JSON to TypeScript interfaces – in the browser
URL Parser & Builder
Decompose, analyze and reassemble URL components
Number Base Converter
Convert between binary, octal, decimal and hexadecimal
Hex / Binary Inspector
Display hex or binary value as integer (8–128 bit), float and string – incl. Big & Little Endian
CSS Gradient Generator
Visually create gradients and export as CSS
SQL Formatter
Format and indent SQL queries – in the browser
Color Contrast Checker
Calculate WCAG 2.1 AA/AAA contrast ratio
Unit Converter
Convert length, weight, temperature, area, volume and more
CSS Box-Shadow Generator
Visual builder with live preview
CSS Border-Radius Generator
Visual editor with live preview
CSS Unit Converter
px ↔ rem ↔ em ↔ pt ↔ vw/vh
JSONPath Tester
Test JSONPath expressions against JSON data
SemVer Bumper
Bump and compare semantic version numbers
PEM Decoder
Decode and analyze PEM certificates and keys
HTTP Header Visualizer
Fetch and visualize HTTP response headers of a URL
CORS Tester
Send HTTP requests and display all response headers
File Transfer Duration Calculator
Calculate the expected transfer duration for files at a given bandwidth
Logic Gate Simulator
Simulate digital circuits with AND, OR, NAND, XOR, flip-flops, MUX/DEMUX using drag-and-drop
chmod Calculator
Set Linux file permissions visually – octal & symbolic
CSS Flexbox Playground
Visually explore container and item properties
CSS Grid Generator
Visually configure grid layouts and export CSS
CSS Animation Builder
Visually create and export @keyframes
Design Token Generator
Export CSS variables, Tailwind config, SCSS and JSON
XML Formatter
Format, validate and minify XML – in the browser
GraphQL Formatter
Format GraphQL queries and schemas
JSON Schema Generator
Automatically generate a JSON schema from a JSON object
MIME-Type Lookup
Look up file extensions and MIME types
Encoding Detector
Detect the character encoding of text and bytes
Random Generator
Generate random numbers, UUIDs, colors and lists
Apache / Nginx Config Generator
Generate web server configs with SSL and proxy