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160+ free online developer tools — JSON formatter, Base64 encoder, UUID generator, regex tester, CSS generator, password generator, and more. No download, no sign-up, runs instantly in your browser.
Format, validate, and minify JSON with syntax highlighting
Compare two JSON objects side-by-side and highlight differences
Export JSON arrays to CSV with nested object flattening
Parse CSV files into structured JSON arrays
Convert JSON objects to XML with pretty-print output
Parse XML and convert to clean JSON
Convert between JSON and YAML formats bidirectionally
Parse URL query parameters into JSON with nested support
Convert between comma-separated and tab-separated formats
Sort JSON object keys alphabetically or in reverse
Flatten nested JSON to dot-notation or unflatten back
Generate a JSON Schema from any JSON object
Convert JSON to TypeScript interfaces instantly
Generate Go structs from JSON objects
Generate Python dataclasses or TypedDicts from JSON
Generate Java POJO classes from JSON
Generate C# classes from JSON objects
Generate Rust structs from JSON objects
Generate Kotlin data classes from JSON
Test JSONPath expressions against JSON documents
Minify JSON by stripping all whitespace for smaller payloads
Validate JSON syntax with error location and structure report
Convert JSON objects to PHP short array syntax
Generate Swift Codable structs from JSON samples
Generate Dart classes with fromJson factories for Flutter
Convert JSON to Ruby hash literals with symbol or string keys
Generate Scala case classes from JSON samples
Generate CREATE TABLE and INSERT statements from JSON arrays
Generate GraphQL SDL type definitions from JSON
Generate Zod validation schemas from sample JSON
Generate proto3 message definitions from JSON
Render JSON arrays as clean escaped HTML tables
Convert JSON arrays to aligned Markdown tables
Deep-merge multiple JSON objects with array strategy control
Convert JSON arrays to newline-delimited JSON Lines
Parse JSON Lines / NDJSON into a pretty JSON array
Strip comments and JSON5 syntax to produce strict JSON
Convert JSON to TOML configuration format
Parse TOML config files into pretty-printed JSON
Find which keys dominate your JSON payload size
Join broken lines into flowing text with paragraph control
Convert code indentation between tabs and spaces
Randomize the order of lines with a fair shuffle
Flip the order of lines from last to first
Spell out numbers in English — integers and decimals
Parse English number words back into digits
Repeat any text N times with custom separators
Flip text 180° with Unicode look-alike characters
Reverse text with mirrored Unicode glyphs
Convert text to Unicode sᴍᴀʟʟ ᴄᴀᴘs
Generate Unicode 𝗯𝗼𝗹𝗱, 𝘪𝘵𝘢𝘭𝘪𝘤, and 𝚖𝚘𝚗𝚘 text
Generate cursed glitch text with combining marks
Convert text to 1337 h4x0r-style substitutions
Spell text as Alfa Bravo Charlie and decode back
Translate English to Pig Latin with case preserved
Collapse, trim, or strip whitespace from text
Remove repeated words, keeping first occurrences
Build acronyms from the first letters of phrases
Sort words alphabetically or by length with dedup
Read text aloud with your browser's voices
13 Unicode font styles from one input
Cross out, underline, or overline text with Unicode
Copy zero-width and blank Unicode characters
Strip all emojis and pictographs from text
Analyze keyword frequency and density for SEO
Convert numbers between decimal and Base36
Convert numbers to the URL-shortener Base62 alphabet
Encode and decode ASCII85 / Base85 data
Encode and decode email MIME quoted-printable
Shift cipher with adjustable rotation and brute force
Polyalphabetic keyword cipher — encrypt and decrypt
Mirror-alphabet cipher — A↔Z, B↔Y
Zigzag transposition cipher with 2-10 rails
Custom monoalphabetic cipher with your own alphabet
Letters to alphabet positions — A=1 … Z=26
Text to raw UTF-8 bytes in hex, binary, or decimal
Convert binary data between Base64 and hex
URL-safe Base64 — the JWT and web token variant
Text to Unicode code points and back
Preview and download images from Base64 strings
Reveal code points behind emoji, including ZWJ sequences
Convert text to octal bytes and back
Francis Bacon's steganographic AB cipher
Strings to JS escapes, char codes, or HTML entities
Normalize to NFC/NFD/NFKC/NFKD and strip diacritics
Convert between Celsius, Fahrenheit, Kelvin, and Rankine
Convert between kilograms, pounds, ounces, stones, and tons
Convert between km/h, mph, m/s, knots, and Mach
Convert between square meters, square feet, acres, and hectares
Convert between liters, gallons, cups, milliliters, and cubic feet
Convert between PSI, bar, pascal, atm, and mmHg
Convert between joules, calories, kWh, BTU, and electronvolts
Convert between degrees, radians, gradians, and arcseconds
Convert between Hz, kHz, MHz, GHz, RPM, and rad/s
Convert date and time between world time zones with DST handling
Days, weeks, months, and weekdays between two dates
Exact age in years, months, and days from a date of birth
Convert durations between seconds, minutes, hours, and HH:MM:SS
ISO 8601 week number and day of year for any date
Convert decimals to simplified fractions and mixed numbers
Convert fractions and mixed numbers to decimals and percentages
Percent of a number, percent change, increase and decrease
Simplify ratios and convert them to 1:n and percentage form
Find aspect ratios of resolutions and scale dimensions proportionally
Convert between decimal, scientific, E-notation, and engineering form
Convert CSV data into clean HTML table markup
Convert CSV data into GitHub-flavored Markdown tables
Generate SQL INSERT statements and CREATE TABLE from CSV
Convert .env files to JSON and JSON back to .env
Convert JSON into PHP array syntax — [] or array() style
Minify JavaScript by removing comments and whitespace
Compress CSS by stripping comments and whitespace
Minify HTML while preserving pre, textarea, and script blocks
Collapse SQL queries to one line, stripping comments
Remove comments and inter-element whitespace from XML
Escape text for JS string literals and decode escapes
Escape and unescape the five XML special characters
Escape single quotes for safe SQL string literals
Format, validate, and re-indent YAML documents
Build aligned Markdown tables from CSV rows or a blank template
Generate a linked table of contents from Markdown headings
Build HTML tables from rows of data or an empty template
Generate iframe embed code with size and security options
Turn YouTube links into responsive, privacy-friendly embed code
Build mailto links with subject, body, CC, and BCC
Create wa.me click-to-chat links with a pre-filled message
Add UTM campaign parameters to URLs for analytics tracking
Generate og: meta tags for rich social link previews
Generate twitter: meta tags for X/Twitter link cards
Generate JSON-LD structured data for SEO rich results
Generate Apache 301/302 redirect rules
Generate the complete set of favicon link tags
Generate MIT, Apache, BSD, GPL, ISC, or Unlicense text
Build shields.io badges for README files
Generate a .editorconfig file for consistent code style
Generate .dockerignore files with stack presets
Convert docker run commands to docker-compose.yml
Turn a URL list into a valid sitemap.xml
Press any key to see its JavaScript event codes
Build cURL commands with headers, auth, and body
Generate SHA-1 hashes from text
Generate SHA-512 hashes from text
Generate SHA-384 hashes from text
Generate SHA-224 hashes from text
Generate SHA-3 (Keccak) hashes in four sizes
Generate RIPEMD-160 hashes from text
Calculate CRC32 checksums from text
Compute SHA checksums of files locally in your browser
Verify HMAC JWT signatures and inspect claims
Encrypt and decrypt with DES or Triple DES (legacy)
Generate bcrypt .htpasswd entries for basic auth
Generate and decode HTTP Basic Authorization headers
Verify text against an expected hash digest
Generate cryptographically secure random bytes
Generate deterministic name-based UUIDs
Generate sortable, timestamped ULIDs
Generate compact URL-safe unique IDs
Generate MongoDB ObjectIds or decode their timestamps
Decode Discord and Twitter snowflake IDs
Identify hash algorithms from their format
Generate fictional US addresses for testing
Generate fictional user profiles for testing
Generate fictional company names and profiles
Generate phone numbers from reserved fictional ranges
Official sandbox card numbers for payment testing
Generate random nouns, verbs, and adjectives
Generate grammatical random sentences
Generate random emoji by category
Roll dice with RPG notation like 2d6+3
Flip a fair virtual coin — heads or tails
Pick random winners from a list
Split names into random, even teams
Generate memorable adjective-noun usernames
Generate rows of realistic records as JSON, CSV, or SQL
Generate brandable domain ideas from keywords
Generate random latitude/longitude points
Generate random nested JSON structures
Turn task descriptions into clean branch names
Format changes as Conventional Commits
QR codes that connect guests to your WiFi
Validate IBANs with mod-97 checksum and country rules
Validate BIC/SWIFT code structure
Validate ISBN-10/13 and convert between them
Validate EAN-8/13, UPC-A, and GTIN-14 check digits
Validate any number with the Luhn mod-10 algorithm
Validate phone IMEI numbers and decode the TAC
Validate vehicle VINs with the check digit
Validate securities ISINs with the check digit
Validate ZIP and postal codes for ten countries
Catch impossible dates like Feb 30 and leap-year errors
Check base64 validity and preview decoded content
Validate hex color codes and show RGB values
Validate JSON documents against a schema
Check XML well-formedness with line numbers
Find unclosed and mismatched HTML tags
Find CSS syntax errors — braces, colons, properties
Validate Kubernetes names against DNS-1123 rules
Validate and dissect Amazon Resource Names
Check branch names against git ref-format rules
Check password strength and entropy locally
Preview and copy every CSS cursor value
Compose CSS filters with live sliders
Build 2D transforms visually
Tune transition timing with a hover preview
Style custom scrollbars for WebKit and Firefox
Pure-CSS triangles with the border trick
Pure-CSS spinners — ring, dots, bars, pulse
Design buttons visually and copy the CSS
Pure-CSS tooltips from a data attribute
Frosted-glass card CSS with backdrop blur
Soft-UI dual shadows — flat, pressed, convex
Organic blob shapes from 8-value border-radius
Wavy section dividers as SVG or CSS background
Gradient-filled headlines with background-clip
Repeating backgrounds in pure CSS gradients
clamp() font sizes that scale with the viewport
Blend two colors at any ratio
Nearest CSS named color for any hex
See colors as colorblind users do
Turn design tokens into :root custom properties
Live Markdown editor with real-time HTML preview
Convert Markdown to production-ready HTML
Convert HTML pages to Markdown format
Count words, characters, sentences, and reading time
Compare two texts and highlight differences line-by-line
Convert to uppercase, lowercase, title case, and more
Remove extra spaces, special characters, and whitespace noise
Deduplicate lines from lists, logs, or any text
Sort lines alphabetically, numerically, or in reverse
Keep or remove lines matching a keyword or regex pattern
Generate placeholder text by word, sentence, or paragraph count
Convert text to URL-friendly slugs for SEO
Reverse text, words, or lines instantly
Find and replace text with optional regex support
Strip blank lines from text and logs
Add or remove line numbers from text
Add a prefix or suffix to every line in a list
Split a string by any delimiter or join lines into one
Extract all email addresses from a block of text
Extract all URLs and links from text or HTML
Analyze word and character frequency in any text
Wrap text at a specific column width
Truncate text to a max length with a custom suffix
Extract specific columns from CSV or delimited text
Encode text and binary data as Base64
Encode or decode Base32 per RFC 4648
Percent-encode and decode URLs
Generate MD5, SHA-1, and SHA-256 hashes
Create HMAC signatures with a secret key
Hash and verify passwords with bcrypt
Strong random passwords with strength indicator
Generate memorable multi-word passphrases
Generate secure random PIN codes
Generate custom random strings with any character set
Generate cryptographically secure API keys
Generate RFC4122 v4 UUIDs in bulk
Inspect JWT header, payload, and signature
Test regex patterns with live match highlighting
Encode or decode text with ROT13 substitution cipher
Translate text to Morse code and back
Convert text to binary (0s and 1s) and decode back
Convert text to ASCII codes and vice versa
Encode or decode Base58 (used in Bitcoin and IPFS)
Encode internationalized domain names to Punycode (ACE)
Encode text to Unicode escape sequences and decode back
Create data URIs from text or encode files as data URLs
Encode text as hexadecimal and decode back
Convert Unix epoch timestamps to human dates with timezone support
Convert cURL commands to JavaScript fetch or Python requests
Convert between HEX, RGB, and HSL color formats
Generate complementary and analogous color schemes
Convert length, weight, temperature, area, and volume
Convert between binary, octal, decimal, and hexadecimal
Convert between Arabic numbers and Roman numerals
Convert between bytes, KB, MB, GB, and TB
Break URLs into protocol, host, path, query, and fragment
Convert images to Base64 data URIs for HTML embedding
Detect your public IP, browser, and screen info
Convert between IPv4 decimal and IPv6 notation
Calculate Unix file permission modes visually
Calculate subnet mask, IP range, and CIDR notation
Parse and compare semantic version strings
Perform AND, OR, XOR, NOT, and shift operations
Look up ASCII decimal, hex, and binary values for any character
Convert px, rem, em, vw, %, and other CSS units
Complete reference for HTTP status codes with descriptions
Parse user-agent strings into browser, OS, and device details
Minify or beautify CSS stylesheets
Minify or beautify JavaScript code
Beautify or minify HTML markup
Escape special HTML characters to entities
Remove all HTML tags to extract plain text
Searchable reference for all HTML entity codes
Beautify and format SQL queries
Format, validate, and minify XML documents instantly
Validate YAML syntax and preview parsed structure
Escape or unescape JSON string values
Generate SEO, Open Graph, and Twitter Card meta tags
Create QR codes for URLs, text, and more
Explain cron expressions in plain English
Convert HTML markup to valid React JSX
Convert SVG to inline React JSX component code
Complete reference for regular expression syntax
Check password strength and crack time estimate
Encrypt and decrypt text with AES-256 in your browser
Generate TOTP codes from a secret key (Google Authenticator compatible)
Generate SHA-256 hashes from any text
Generate MD5 hashes for checksums and fingerprinting
Generate cryptographic salt values for password hashing
Build and sign JWT tokens with a custom payload and secret
Encrypt or decrypt text with a XOR key
Build a Content Security Policy header with a visual UI
Generate RSA public/private key pairs in the browser
Generate random integers or decimals within any range
Generate random dates in any format and range
Generate fake email addresses for testing
Generate random first and last names for mock data
Generate random IPv4 or IPv6 addresses
Generate random MAC addresses for network testing
Generate random HEX, RGB, or HSL colors with previews
Generate .gitignore files for any language or framework
Build robots.txt files with a visual UI
Generate package.json with all common fields
Build cron expressions with a visual picker
Generate SVG placeholder images with custom size and color
Convert text to large ASCII art banner fonts
Generate complementary, triadic, and analogous color harmonies
Validate email address syntax with detailed feedback
Check URL format and parse components for validity
Validate IPv4 and IPv6 address format
Validate MAC address format in multiple notations
Validate UUID format and detect version (v1–v5)
Validate credit card numbers with Luhn algorithm (no data sent)
Validate international phone number formats
Validate domain name and hostname syntax
Validate cron expression syntax and preview next runs
Validate semantic version strings and compare versions
Build linear and radial CSS gradients visually
Create CSS box shadows with a live preview
Generate CSS border-radius values visually
Build CSS flexbox layouts with a visual editor
Build CSS grid layouts with a visual editor
Generate CSS text-shadow effects with live preview
Create CSS keyframe animations with a live editor
Generate CSS clip-path polygon shapes visually
Calculate and compare CSS selector specificity
Check WCAG color contrast ratio for accessibility
Generate tints and shades from any base color
Pick a color and get HEX, RGB, and HSL values
Browse all Tailwind CSS color palette values
Browse all Material Design color palette values